This is the MTD lawn tractor I had delivered from Amazon. kzfaq.info/get/bejne/mcyJopqW1JbQaYU.html

I had a 1981 corvette. I built the engine myself and only used synthetic motor oil. Over 40,000 miles of extremely hard driving, driving that would crystallize a new set of brake pads in a couple of hours. When I took the motor apart it was as clean as the day I put it together. Bearing clearance unchanged. I only use synthetic oil, that sold me.

I've put synthetic in everything from cars trucks motorcycles Small engines etc and it's always worked fine for me.

As a master engine and compressor technician I will give it to you simple. Do not use synthetic lubricates while breaking in an engine " seating the rings" but after that it is preferred in almost every situation. The reason is simple. synthetic oils are very good at what they do so you tend to see incorrect crosshatching take while using them to cut the rings. this causes a glazed cylinder and poor oil retention after a few hours of the breaking in. Sometimes the glazing is so bad re-ringing is required. Use petroleum oil for break in and synthetic from then on out. Ingersoll Rand master Technician XLE.PHE.Type 30 over 28 years and 22 years master Diesel mechanic for Ingersoll Rand , Wakiesha, Caterpillar, and Caterpillar energy division. department of energy consultant for emergency generator operations and reliability.

I'm 70 years old, I spent 4 years at GMAD (General Motors Assembly Division), 1978-1982, I spent 15 years as a chev mechanic at an Atlanta Area dealership, also spent 2 years at a phone center processing and ok'ing under 600.00 auto repairs for a Automotive Protection company, I've researched synthetic oil for over 10 years and have used either Mobil 1 or Amsoil 100% synthetic motor oil since 1978. So I've used synthetic motor oil for 44 years without 1 single oil related failure. So I doubt that you'll have much luck changing my mind. I don't have a tractor.

I’ve used 100% synthetic from new to 300k plus. Absolutely ZERO problems. Mobil Extended Performance is awesome!

What that tells me is that synthetic oil is far superior to conventional oils. If the engine won't "break in" with synthetic then it isn't wearing any of the engine parts. An engine "break in' is the wearing of the cylinder walls and rings also called "seating" the rings. I use synthetic oil in everything I own and have for many years. I change my own oil and ship a sample off to Blackstone Labs to have it analyzed for wear metals and contaminants. 130,000 miles on my Town and Country, 75,000 miles on my wife's Honda CR-V, 19,000 miles on my Harley Davidson and every oil analyzation has come back indicating no wearing metals or contamination. My Harley and CR-V came from the factory with synthetic and will see nothing different as long as I own them. One other thing, I rather think Kohler lawn tractor engines are not manufactured to the same specifications as todays automotive and motorcycle engines.

I've used synthetic oil in all my engines for the last 20+ years with no problems.

Reason manufacturers say dont use synthetic oil is it makes your engine last too-long bad for repeat. Business

There has been many study’s on this. Synthetic works so well that the manufacturers want you to break in with conventional because it allows wear. Synthetic slows the wear down so much it takes much longer for break in.

Steve, get a hot plate. Find two pans you don't care about. Pour synthetic in one and conventional in the other. Apply heavy heat to both until they evaporate but not catch on fire. The synthetic will almost completely evaporate other than the additives and the conventional will leave behind sludge. In modern engines that sludge builds up over time and restricts engine seals from conditioners in the oil that keep them from cracking and leaking oil. Need a reference for my rant? My entire family attended a college just northwest of Houston that has one of, if not the best petroleum engineering programs in the world. You have no idea what you are talking about and are going off of what small engine manuals are saying. In every conceivable metric, synthetics have a higher specific heat capacity, have better viscous characteristics, and protect better before the additive package is even considered. Honda, Toyota, and many other mainstream manufacturers are all calling for synthetic from day 1. They want to require it for two purposes. 1) It protects the engine better and reduces the amount of warranty claims. This reduces their liabilities. 2) People that cheap out can be denied warranty claims, reducing their liabilities. There's a thousand tests on KZfaq regarding the capabilities of synthetic vs conventional, but God bless you for reading a paperback manual. "Here's your sign..." - Bill Engvall

Synthetic oil is much better than natural oil in every case. Synthetic oil will break down less and has a much tighter bell-shaped curve. My engines last forever. I only use synthetic oil.

I've used mobil-1 synthetic since 1974 approximately in all my vehicles including 2 stroke engines. Never ever have i had a problem

The reason for using standard petroleum oils for break in is, the film strength of synthetic oils is 6 times stronger than petroleum based oils and the rings need the friction to "wear in" and seat properly. With the higher film strength the friction is reduced and break in takes much longer. The lower film strength of petroleum based oils allows for more friction and more wear on the ring/piston surfaces which enables a faster break in.

I have used synthetic oil for my Toyota Camry 2009 since day one and it's been with me for 12 wonderful years. I haven't experienced any problem with its engine. It has been running like new. No leakage, no unusual engine noise, and no deviation from its usual maintenance.

Modern engine piston rings are designed with synthetic oil in mind.

My dad monitored his gas mileage religiously. He changed his own oil as well. One time they didn’t have the regular oil at his viscosity. He bought synthetic oil instead. He found out he got 2 mpg better gas mileage. He had a Silverado v8. Synthetic is a superior blend of oil.

20 years ago when engine block bores were finished they needed to be worn in or broken in because the tool marks had to be smoothed out by the piston rings for a good seal. The engines that are bored in the last 20 years have this additional finishing operation called plateau honing which artificially breaks the engine in. It smoothes out the top surfaces of the tool marks and prepares the bores for sealing without breaking in.

They want you to use conventional oil at first because it allows a tiny bit of wear to break in the engine. The synthetic doesn't provide enough friction to break in the engine. That should tell you which you want to use in the long run.

I have used Mobil 1 since I bought my 2006 Silverado, with 40k Miles, in 2009. I have 511,000 miles and still going here in 2024. I even tore down the top end in 2018 for a ticking noise and replaced the lifters and push rods (found bent push rods) and the motor was clean inside. I change the oil regularly as I do all the maintenance. If anyone else has this issue with the 5.3L Gen 3 engine, I recommend replacing with the LS7 lifters and chrome molly push rods.

I’m a retired Mobil lubricant specialist for 35 years. Some equipment manufacturers can recommend mineral based oils before using synthetic because mineral oil creates more friction and wear than synthetic oils…so the 1st few hours is for the settling of the moving parts. Use mineral oils If there were no break-in done by the manufacturer. If there was a break-in done, then you can start with synthetic right a way. Kholer or any other small engine doesn’t need synthetic oil. Mobil 1 in those engines is an overkill. Synthetic PAO based Mobil 1 is excellent for any cars and Mobil Delvac 1 ESP is the same for heavy trucks and machineries.

The reason some new engines spec synthetic oil from the start is due to the new “plateau honing” process used to finish the cylinder. In the old days when a cylinder was bored and then honed the honing would leave a cross hatch pattern with microscopic sharp ridges in the cuts that lay in the cross hatch pattern. When you started the engine for the first time these sharp ridges would lay down or flatten to some extent leaving a fairly smooth surface with a small cross hatch channel that holds oil for lubrication. This would be your common break in as the rings wear into the cylinder wall flattening the sharp ridges and seating to the surface that remains after. This is also one reason why it was important to change oil fairly soon after break in period. Now with modern technology the honing process has been modified with what is now referred to as plateau honing. In this process the same cross hatch pattern is cut into the cylinder but a final process with a plateau hone follows laying over the sharp ridges left by the honing process leaving a perfect surface for rings to ride on and receive perfect lubrication, maximum seal, and less friction. This is the new process that allows engines to run with little to know break in as the rings are basically installed into a perfect ring seal environment before the engine has ever even been started. This along with hydraulic rollerized valve train make break nothing like what it once was. Not every manufacturer is utilizing this technology and not every engine uses valve train that allows for this either. Hope this helps and great video!

LOL I worked as a contractor for Castrol Oil few years ago. The comments of all self-proclaim experts on here is more entertaining than a good movie!!!

My 17 yr old daughter had a 78 buick. Engine locked and stalled her on highway. Called me to pick her up . Got to her location checked oil, nothing on stick, I had one quart of mobil synthetic in truck. I dumped that in and started the vehicle. Without a problem, we drove back to home, i changed oil and filter complete. Drove car for two years and sold it. Car is still is on the road as i know, I'm sold on synthetic oil for all my engines large and small.

Used Mobil 1 in everything zero problems in the last 15 years

I have been using Synthetic Oil for the past 16 years with my Toyota Tacoma.

That manual was probably written 20+ years ago. I use synthetic, AMSOIL in everything I have.

Been using mobile one for at least 25 years, no engine issues from the oil, engine SO clean inside

The reason you need to break in a new engine on the break in non-full synthetic is because. Synthetic oil has such a superior, film, strength, that the rings can not scratch themselves into fitting the cylinder perfectly. You have to use the oil with the not so good lubricating film strength to allow the piston rings to contact the cylinder walls so that the rings will get polished/worn into the proper shape conforming to the bore… by the way. All multiweight oils, Whether they are labeled as full, synthetic, semi synthetic, or not labeled as any synthetic, they are actually partly synthetic. To get the multi different weights, they have polymers added..Polymers are synthetic. 10 W 30 motor oil has polymers added to give it that multi temperature rating. It acts like 10 weight oil at the low test temperature set by the API, and it acts like 30 wt at the upper test temperature. 10W-40 motor oil has more polymers than 10W-30 to get that wider range ..To get that multi temperature rating, the oil has polymers added, the wider, the spread ratio on the weight, the more polymers are added to the oil. I have been using mobile one oil in my cars and trucks since I believe the 1970s was when that first appeared on the market. The advertisement pitch they used was, the once a year or 25,000 mile oil. I liked that so I switched to it. I only change my oil once a year and I do not use fram filters or any other filters that has fram make their filters for them.. I use Purolator filters mostly. And I generally put less than 10,000 miles a year on my vehicles. I have never had an oil related failure in any of my vehicles… One of my vans I bought new in 1977, I had that van for 31 years. And it drove away when I sold it to a scrap yard… I never add aftermarket additives to oil, and I always use the required weight of oil. I let my oil completely drain for hours, sometimes overnight. You would be amazed at how much oil continues to drip from an engine overnight. I only change my oil after I have had the vehicle running on the highway not in the driveway for at least an hour. The detergent in the oil. keeps the grit, gum, soot, acid, metal particles, sludge, and corrosion, suspended in the oil, so that it can be flushed out when you drain the oil.. I also attach a powerful magnet to my drain plug. I do not use high mileage labeled oils. Those oils sometimes have additives that are designed to make rubber gaskets and O-rings swell up hopefully to reduce or eliminate oil leaks in high mileage engines… I always always always fill the oil filter with fresh oil to burp the air out of the filter element so the engine does not starve for oil on a start up after draining waiting for the oil filter to be filled by the oil pump when the car starts.. I have never had anyone, but me change the oil in my vehicles ever. Because if you go to a place to have your oil changed, they are not going to let the oil drain even for five minutes. If you drop your car off to have the oil changed somewhere, they may let your car sit for hours, until the engine is cold, and all of the contaminants suspended in the detergent of the oil will settle in the sludge at the bottom of the engine again, and it will not come out when they pull the car in cold and drain the cold oil. I drain my oil when it is so hot, I will have the car running. When I get home, I will leave it idling, while I get the tools and the oil pan to catch the old oil in place, then I shut the car off and pull the plug while it is too hot to handle… I leave the hood of the vehicle opened while the oil drains so that I don’t forget that there is no oil in the engine yet. I have known people that have drained the oil and forgot to put the oil in, and they drove away… so don’t think just because you are buying oil that is not labeled synthetic. That it is not synthetic. If it has a multiweight rating, it is partly synthetic. If you have a new car or motorcycle. It’s best to use the oil specified by the manufacturer. Especially the oil filters. I have seen Honda reject a warranty fix on a Honda Goldwing motorcycle because the owner was using a Chinese made chrome oil filter… The owners manual of every motorcycle I have seen, I’ve worked in the motorcycle industry for 17 years, every owners manual specifically states to use OEM parts, which includes filters.. that customer that had that damaged engine that Honda refused to repair because of the cheap aftermarket oil, filter, failure, that customer ended up buying a salvaged engine from a salvage yard, and he paid to have that engine installed even though his motorcycle was technically still under warranty.. The most damaging time for any engine, is a cold start up. Because the fuel mixture, weather, fuel injection or carburetor, is Rich. And the cylinder walls are cold. So the incoming fuel condenses on the cylinder walls just like humidity condenses on the outside of a glass of iced tea in the summer. That condensed gasoline. dilutes the engine oil and rinses the lubrication that might be on the cylinders walls away. It is especially true on water cooled engines because those cylinder walls stay cold longer until the engine water around the cylinder jacket warms up… The government got car manufacturers to agree to say that it is OK to drive your cold car as quickly as 15 or 30 seconds after starting it. I wouldn’t do that. Engine oil takes as long as 45 minutes to get up to operating temperature at times.. engines don’t wear out, they are neglected to death..

Since 1993 I've been using Mobile One oil in all my new cars. My 1998 Ford F+250 with a 4.6L, I bought New with 68 miles on it. Now it's a little rough on the body but 380,000 miles later and the engine still runs and starts like new. Always well maintained and always Mobile One oil. My 2012 GMC 2500 I bought new, now has 153,000 miles also Mobile One. And My 1993 Honda Civic I got new right after college. Now my niece drives it with over 350,000 miles on it before the odometer stopped working also started its life on Mobile one too.

I’m a Koehler generator tech, all we use is synthetic lol

A modern automobile engine is built with low tension rings that are extremely precise, and as near perfectly round when installed as possible. The top ring is for cylinder sealing, the second ring is no longer considered a compression ring, rather it is used to scape oil downed away from the piston, and is actually tapered; wider at the bottom than the top. The oil control rings and collector get most of that done still. But today’s engine metallurgy is so good that the rings are round, the cylinder is round, and not of these parts wear, or break in, so synthetic oil is fine, right from the start. Lawn mower engines are pretty old tech. The cast rings and low quality cylinders really do need to break in to each other. Just like airplane engines. Old tech. So a basic mineral oil is best to get the break in done. Another thing about the oil you use. Zinc, dialkyl, not diary, is only necessary where points of impact is extremely high is concerned, that’s the only place that’s neededRocker tip tp pushrod or to vale tip, flat tapped lifters to cam. Synthetic oil pretty much does that for you. And running synthetic oil where leaded gas is used is not recommended because the spaces between the molecules of the synthetic oil are too small to scavenge the lead with an oil change. The lead then stays behind and causes all kinds of problems, like centrifuging in the crankshaft lube holes, blocking them off. That’s why some manufacturers pulled their synthetic oil for aircraft use. I am retired from GM Engineering and trading, and past member of the SAE.

When we built older hot rod engines with Chromoly rings back in the day, we always broke them in with conventional oil. We usually ran Pennzoil because it is pretty poor oil and really allowed those ring packages to seat. Newer engines come with low drag, low tension rings for better fuel economy (speaking of passenger cars and trucks). They will break in fine with synthetic oils. Synthetic oils do last longer as far as break down, but they get dirty and contaminated just as fast as conventional oils. As a technician and OEM automotive instructor for 32+ years I have learned to run Synthetic oil on high performance or engines with power adders (supercharger or turbo), but still change the oil at a 3 to 4k interval because of normal consumption and the oil becoming laden with acids and becoming contaminated with byproducts of combustion. Synthetic oil is superior oil, but a waste of money if it is not needed because it DOES NOT allow extended service intervals in my professional opinion. The biggest problem newer engines face is carbon due to oil burning in the engine from the PCV system causing buildup on Intake valves and causing piton rings to stick to the ring lands of the piston. These issues cause drivability and oil consumption problems because the rings no longer have sealing tension against the cylinder wall, and carbon on the valves absorbs fuel from the injectors. I solve these issues with professional strength engine de-carbonizing chemicals ran through the intake manifold and fuel injectors. I also run catch cans on my PCV systems to capture the oil that causes these conditions. Just my personal observations over the last three decades.

Mobile one in Honda Odyssey 480,000 still runs great and changed every 7-8,000 miles

My brother bought a used Toyota Tercel years ago. After he bought it, with about 60K miles or so, he changed the oil to Mobil 1 synthetic. Years later, after about 275K miles, he called me over to help fix an oil leak. The valve cover gasket needed to be changed. When I pulled the valve cover off, the internals looked like they were Brand New! I've been using Mobil 1 in everything I own since then. It's Never let me down.

I have been in the landscape industry for over 40 years. In that time, we have always used Amsoil in our trucks. Opti-4 in the four strokes and Opti-2 in the two strokes. Along with that, we put Star Tron in all the small engine fuel. Never have had an oil related problem in our machines. Also never have had any fuel related problems. I know everyone is different but that is my experience with small engines and trucks.

My CLK serviced by Mercedes has only had Shell Ex 5 40 oil for over 200,000 miles with no Engine repairs , the modern oils have improved a lot over time

I’m an old man who has used a lot of mower engines and my Koehler has been the best engine ever. When time comes to changing the oil it still looks gold. Amazing engine 👍🏼

I have been using Mobil1 5w-20 synthetic for the pass 15 years on the same truck, couldn't been happier and I only change oil, filter and air filter every 12.000 miles...

for more detail for those that dont know. new engines have cross hatchings roughed into the walls to act like a cutter on the piston rings. this grinds down the high points of the pistons rings so they wear into the cylinder wall shape. this closes any gaps, creates a better seal, increases efficiency and reduces blow by and oil consumption. synthetic is a better lubricant that reduces the cutting process, the hatchings smooth out over time so if the rings arnt cut enough before the sidewalls smooth then you will have a worse off engine. its ok to use otherwise. also adding pressure to the cylinder like mid range acceleration helps break in as the cylinder pressure pushes the rings out harder towards the walls better helping the break in, thats why going too easy and letting a new engine idle for too long is bad.

Literally all I use. All my vehicles are 200k-400k miles and zero issues.

years ago.... my father was an engineer at GM. They set up SEVERAL motors in a huge room and just let them run until they "locked up". He was all smiles when he told me Mobil 1 was the only one that didn't lock up. That motor just kept going and going.

Synthetic oil differs only in base oil It’s molecularly perfect where conventional is full of contaminants and is sheer unstable due to differing sizes of the molecular structure

I have a push mower I bought from Sears in 2010, has a B&S platinum engine. I've used nothing but synth in it and it starts first time in the spring with one pull. I also use non-ethanol gas too. It runs super great!! No leaks of any kind and it does not burn any oil that I can notice. The syth oil I use is specifically for lawn mowers. Not for cars.

Normally when you buy a lawn tractor or a garden tractor, it COMES WITH engine oil already in it. So put in whatever you want when you change the oil after the break-in period. I don't have a problem with synthetics. In the military we used 'synthetic' in all our CH-46D helicopter transmissions. No problems.

Back in 1990 I bought my first used 1988 Chevy Silverado V8 305 engine with 160k miles here in California and the first thing I did a good oil flush and put Mobil 1 synthetic oil I drove it until it had 310k miles and I never had any oil leaks or any problems it passed the smog inspections it always run smood I sold my truck to a friend of mine who was always bugging me that he wanted to buy my bad ass truck because I painted in a Viper yellow color so I sold it to him then he moved to Texas to this day he still has that truck with the same engine... Synthetic oil rocks!!!

With new motorbikes: I was told by my dealer that they had stopped using synthetic oil for a new engine simply because the oil was so good that it didn't allow the pistons etc to bed in. After this period I would suggest that synthetic is better for protection. The manual that you are referring to basically says the same thing.

Newer cars and trucks come from factory with synthetic. Newer engines use low tension piston rings to increase mileage. Use of regular oil will destory the engine .Synthetic shines at startup and cold weather

The added friction from running conventional oil is beneficial during break in so that the outer circumference of the piston rings can wear to the exact profile of the cylinder bore, since they may not be a 100% perfect match out of the box. After that is achieved, switch to synthetic to prevent any further wearing of the rings, which would cause ring end gap to expand and compression to drop.

I've been using synthetic oil for twenty years in my 1995 ford van. I have 422k miles on the original engine. Never been rebuilt!

We purchased a 2003 Ford 5.4L F-150 SuperCrew 4x4 with only 5,400 miles on it. It came with Mobil One Full Synthetic in it. I always replaced it with full synthetic 5W20 as RECOMMENDED in the owners manual, specifically Mobil One brand. At roughly 70,000 miles when changing oil and filter, I failed to notice the oil filter seal remained stuck to the engine block. When the new filter was installed, it naturally failed to seal, but not noticing it, I drove it 35 miles home that night from my son's house. The problem was discovered the next day when checking the dip-stick, I noticed it was bone dry. Yep, no oil in the engine. I removed the filter, discovered the root-cause, fixed the problem, and promptly put in an additional 6 quart of Mobil One Full Synthetic oil, and cranked it up and drove it. Several years later, after numerous additional oil and filter changes (yes, done properly without repeat incident!!) when we sold that truck with 300,000 miles on it, the motor was FACTORY SEALED. The engine had never been opened since that truck left the factory. The only work ever done in the engine bay was to replace the alternator once and the battery twice; but the engine remained FACTORY SEALED at 300,000 miles. The valve covers had NEVER been off that engine. I have never heard of an engine going 300,000 miles and remaining factory sealed. I understand that it is still being driven since having sold it. So, when you declare no one should use Mobil One or any other brand of full synthetic oil, I ask why and what's the difference between your experience and mine? But I am sold on full synthetic motor oil and will never switch back, at least not until someone testifies they've run an engine on regular oil for 70,000 miles, drained the oil out it, ran it 35 miles with no oil, then put regular motor oil back in it, and it last and additional 230,000 miles while remaining FACTORY SEALED. When you do (or anyone does) that, then I'll listen. In the meantime, I run premium grade full synthetic. And my preference, is Mobil One Full Synthetic.

I run mobile 1 full synthetic in everything I own. Except my 2015 International Lonestar semi with an ISX Cummins and it gets Rotella T5 semi synthetic. My 2017 Chevy Silverado, 2001 Dodge Dakota, 2011 Toyota Tacoma, 2018 Toyota Corolla IM and my Husqvarna 22hp Briggs 54” cut zero turn. NONE OF THEM have ANY leaks, 0 oil consumption. And I change the vehicles every 5,000 and they all still look gold. Dodge has 213,000 miles, Tacoma has 94,000 miles, Silverado has 60,000 miles, Corolla IM has 42,000 miles, and lawn mower has 110 hours. ZERO PROBLEMS. And the semi has 559,000.. zero issues there too and 0 consumption.

Full synthetic on a Suzuki swift. 11 years old, 340000 klms on the clock. Still runs great and doesn't burn oil. Enough said.

I’ve been using mobil 1 full synthetic oil for nissan maxima 1995 and no problem. Now i got 488,880 milesage in it.

Been using left over synthetic from oil changes in my lawn mower and snow blower for years. Marvel mystery oil added to fuel and oil every so often too

STD break in petroleum based non synthetic motor oil has been known about for over 40 years. I've always considered it common knowledge in gasoline and diesel powered engines and the enthusiast owners. This is why they don't recommend early oil changes on new motors. Run the engine the proper amount of hours or miles on the break in oil. I'd even go so far as to use a regular petroleum based motor oil for your first oil change, too, before going to a full synthetic motor oil.

I use synthetic in everything. My son ran out of oil and drove until it wouldn't go any farther. Fixed the leak. Filled it back up with synthetic. Started it and drove 20k more miles

My car comes from the manufacturer stating to USE synthetic Mobil One Oil. Since 2005, I have had ZERO problems with my car(Nissan 350Z). In fact, I now have 283,000 miles on it with no issues and, no oil leaks, smoking or extra oil consumption. ....... Do your own thing folks !

Going on 300000 miles on my old ford f-150. Still runs great. Have always used only synthetic oil.

Mobil 1 is all i use on all my vehicles, I was using it in my 94 Honda Accord that was still running when I donated it to a non profit, original engine and transmission. The transmission was starting to slip and that is why I bought a 2014 Toyota Avalon, which still runs like the day it was brand new. My Nissan Frontier and Avalon use Mobil 1 oil and nothing else, full synthetic of course. Maintenance is very important.

After breakin syn.oil will give the best protection.....period! I have raced both 2 strokes and 4 strokes and have done constant internal checks on the engines. Synthetic oil shows FAR LESS WEAR than mineral based oils.

I've been using mobile one in all my rigs for over twenty years and have no problems ever! I have four Harley's and same thing no problems with them either.

Synthetic oil is used by everyone in cars and trucks up here in interior Alaska where it is -40 every winter....conventional 5W30 pours thicker than honey at -40 while 5W30 synthetic pours easily at -40 degrees.

What he states is true. There has to be a wear-in (where they actually wear out a little) period for the piston rings to seal to the cylinder walls. After that period is when you want as little wear on them as possible for longer engine life.

My 95 Ford Explorer had synthetic installed for the first oil change at 2,500 miles and every 20k after. It went 15 years and 232,000 miles with no engine problems or oil consumption. Still ran fine the day I drove it to the crusher because the frame was swiss cheese and most of the sheet metal rotted away and the trans was starting to slip.

I did engine and manual transmission rebuilds, and worked on some high performance cars. When the engine is newly built with the cylinders re-bored and with new rings, bearings, and etc., it is best to break in the engine with regular oil. Conventional oil allows for normal wear on a newly built or rebuilt engine. With cars it is best to drive the car for about 4000 miles before making its first oil change. Use conventional type oil for another 4000 miles. Then you can go to synthetic oil for the rest of the engine's life. It is important to change the oil at normal intervals. This is to clean out carbon that gets in to the oil, and clean out any pollution or dirt that may get in to the oil. Through the life of any engine there will be some very fine microscopic size metal particles from normal wear. Changing the oil rids of them. As the oil is used and ages it also starts to change its lubrication qualities. I like to change my oil every 6000 miles or ever6 months whatever comes first. I use synthetic oil only. I use the type of oil recommended by the manufacture. Many of the auto manufactures now break in the engines at factory before installing them in to the vehicles. They do the break in using regular engine oil. Then they change the oil for synthetic oil when installing the engine in to the vehicle. When receiving your new car, even though the dealer may tell you the engine is broken in, it is best to go easy on it for the first 4000 miles or so. Drive at varying speeds, and don't use cruise control. Avoid letting the RPMs go past 4000. Go easy on the starts. Avoid hard acceleration very often. Don't tow heavy loads. The transmission and drive train have to also be broken in. After the vehicle is past 4000 miles or so and is working on synthetic oil you can drive it how you want. Like anything with engines and drive trains, if you very often kick ass on the vehicle you will reduce the life span of the engine and drive train. Avoid spinning the tires when starting off. This plays hell on the transmission and the differential. The drive train is designed to be able to take a lot of forward torque. It is when the tires stop spinning there is the reverse torque effect to the drive train for a few milliseconds (few thousandths of a second) even though the vehicle is moving forward. It is at the instance where the wheels stop spinning that the bearings and gear teeth take the huge amount of shock. Because the isometric torque affect on the output shaft of the engine and transmission is very high when accelerator is pressed down very hard this is where there is greater wear of the seals. If you want to greatly increase your engine and drive train life span to be in your favour drive the vehicle easy. Drive it like you are driving a limo. Go easy on the starts and go easy on the stops. You will also save a lot of fuel, tires, and break maintenance cost.

Back in the late '70s a car magazine ran a test on the then,0new Mobil 1 oil. The took a brand-new Corvette, filled it with Mobil 1, and ran it for 50,000 miles. At that point they tore down the engine for inspection and found the cylinder walls still had the hone marks on them. It was recommended not to use M-1 on a new engine but highly recommended it after a break-in period. I used it in my Toyota after it had 10,000 miles on it and the mileage jumped from 28-29 MPG to 33-34 MPG and the normal operating temp dropped noticeably. Good stuff but will slow a break in.

everything is clear here. synthetic oil has too good lubrication specifications and during the first 50 hours, the engine must rub/grind, therefore, for the first 50 hours, a lubricant with poorer lubrication properties is recommended. After the first 50 hours, you can use synthetic oil and the engine will be better from that. Of course, changing the oil will be twice as expensive :)

My Chevy Cobalt engine lasted to 345,000 miles before some idiot tboned me. It would have easily reached 400,000 miles. Used Mobile 1 5wx30 full synthetic after the initial 30,000 miles.

I've been using synthetic oil in all my cars since mid 90s, including my first car which was built in the 60s. I prefer the 5-6k miles change intervals rather than 3k. Since my newst car has 98k miles already, and my oldest had 385k, I don't think it's a problem.

The reason that you don't put synthetic oil in new IC engines is because the oil retains viscosity and lubrication qualities better than natural oils, mostly because of the structure and length of the long carbon chain molecules that make up the oil. Synthetic oil will not allow for the wear that is needed to allow the rings to seat and seal against the cylinder wall. Even 45 years ago, when Mobil brought out their first synthetic oil product, tear down of the test engines they ran it in for publicity showed that the machining marks on the cylinder walls were almost fully intact after 200,000 miles. Especially now that piston ring tension in the new low pressure engines is lower, and because of fairly loose machining tolerances in all of the engine makers, they rely on break in seating of the rings to provide vapor and oil sealing. Basically, you are performing the final machining of your engine piston rings in the break in period. Once the car is broken in properly, the use of synthetics would appear to limit further bore and ring wear much better than oils derived from crude oil sources. Plus, the added bonus to be enjoyed is that the synthetic product will retain lubrication properties superior to regular oil because even as it breaks down, the synthetic molecule chains will remain longer and more efficient, making it possible to put 10-12K miles on it before you have to replace it, as opposed to 3-5K miles for regular oil. You have to change filters regularly, though.

I have used Mobil sinc 1998 in a vehicle I own. That vehicle now has 188,000 miles on it and is still running fine.

I use synthetic oil in everything, although all those engines were broke in on standard oils. Never a problem with any of the engines

I use Full sythetic not synthetic blend . If your leaking oil it’s because you have a leak .full synthetic won’t leak if you don’t have a problem in the first place if your already leaking then keep using the same .just flows better .

In the late 1950s many engines were ruined with people thinking HD meant “heavy duty” ! It meant “high detergent” and old engines were ruined when oil return holes were stopped up with the old oil.

Amsoil 100% synthetic high mileage 0w20. 5 to 8k no leaks. 3 years running. 193k miles now.

Anyone that spends any time working on gas engines knows that you never break in a new or rebuilt motor on synthetic. This is nothing new. Synthetic will not allow the rings to properly seat. That in itself should tell you how good a quality synthetic oil is. I purchased my Cub Cadet 1864 new back in 1993 and after the break in period I have switched to Mobil 1 10w30. After all these years the engine still has good compression and when I do need to go into the motor, mostly to reseal the valve covers there are no deposits and the inside still looks brand new. Dean

Full Synthetic oil works amazing in anything!

Steve i bought a 2006 cadillac cts mobil 1 was recommended, on the oil filler cap it says mobil 1 i could drive longer before oil changes .

That is common knowledge ,rings have to seat . Same thing for roller cam hot rod engines have to run on regular oil an hour or two . Synthetic will take longer to seat but not an issue

I used to be in the oil change business some 22 years ago. The amount of oil an engine uses will vary from car to car not just a toyota camry to a chevy impala but camry to camry. The internal combustion engine uses oil to lubricate the cylinder walls and does get used here. The average usage in 3000 miles is half a quart. On first 3000 miles you can have a usage of nothing to most of the engine oil. Not every engine off the assembly line is the same. I knew a couple guys who worked at the Chrysler Foundry in Indianapolis, In. where they made the engine blocks. They told me NEVER to buy a Chrysler or Dodge with the engine they made. That plant was closed a while ago so things may be different. This is where the difference comes is in manufacturing. How well an engine is made makes all the difference. Seventy years ago you put the heaviest oil you could get because engine tolerances were nowhere near what they are now. Instead of 20w50 Ford has a 0w20 in some of their cars. This is because the oil needs to go through small places to lubricate. Back in the day there was an additive called Slick 50. It coated the oil passages with PTFE. Basically the same thing that makes non-stick cookware non-stick. They say if you use their product according to directions they guarantee you engine will last 250,000 miles. I have a GMC in my driveway that just turned 261,000. nothing special was ever done to it. Regular oil changes. Synthetic oil is really expensive. Too expensive for me. Besides, we wont need to change oil in cars for too many more years anyhow the way things are going with crack pot in the White House.

synthetic oil can leak. it isnt a problem with the oil, but a problem with the seals and gaskets. the synthetics can get through smaller spaces so leaks will occur. also some of the additives can react with the seals and make them soft and cause failure. synthetic oil is 'engineered' in a way that makes the oil particles a more uniform size, so it works better to prevent friction, seating in rings sometimes requires some friction and if you use synthetics, it takes alot longer to seat rings etc. so, use conventional oil to break in an engine and then switch to synthetic. you should change the oil on a new engine (in a car etc.) at 300, 600 and 1200-1500 miles anyway just to get rid of anything that might have not been cleaned out before initial startup. bits of lint from rags, assembly lube, cause that stuff clogs filters (yes change the filter with the oil!) and then, when everything has bedded in use synthetc oil, cause it prevents friction better and less friction means more power.

If you claimed "do not use synthetic oil", then you have to had better proof than just this video clip. Do some research on the "base" of synthetic oil regarding what it is made of before making this video clip.

I have a 2003 Chevrolet Silverado Z-71 truck, and it has had a Mobile One full synthetic oil in it since the day it left the car lot. No problem from the oil.

I put synthetic oil in everything except my coffee

Wrong. What they are saying is reg. oil wears MORE than syn. You want the rings to wear a little at first to get a good fit against the walls of the cylinder. but all in all syn. oil is better. Fifty years ago I read a test that Popular Mechanics did with "Mobil One". They put it and reg oil in two test tubes. Stuck it in liquid nitrogen. Reg. oil froze. Syn. oil stayed the same viscosity. Then over a Bunsen burner. Reg. oil turn to sludge. Syn. stayed same viscosity. The good thing is it will run for 50,000 miles between o/c. PM did it and the test motor still had honing marks on the cylinder walls. Not that that matters in a lawn mower.

It’s because the synthetic lubricant is so good that the engines moving parts can not wear in to a married perfect fit during break in time. After break in time it will be better not to have the wear so it’s much better to use the synthetic oils for no wear at all. This is all the manufacturers are trying to do b

I have run synthetic oil, since the mid 70s, in all my Harley Davidson air cooled engines, AFTER BREAK IN. When rebuilding these engines, all parts showed MUCH less wear than engines I've torn down that used regular Harley Davidson brand oil. My current Harley, I switched to Synthetic (Amsoil) at 3000 miles. I noticed a big difference in audible engine noise after the switch, (Harley valve train components are known to be noisy), and acceleration seems smoother and more "effortless". Put synthetics in primary/clutch, and transmission. Reduced noise and smoother, less "clunky" shifts, and clutch engagement in very smooth. I've used synthetic oils, (Redline brand), in my Camaros and Pontiac Formula cars with many power mods over these last 45 years, with zero problems. In my experience the synthetic oils offer outstanding wear resistance. In every instance, for engines, transmissions, and differentials, these fluids have performed flawlessly, using normal change intervals.

The reason for this is, molecules that make up the oils are arranged differently. Conventional oil molecules are arranged into a sort of clump where as the synthetic oil molecules are arranged into a linear chain. This is where many myths come from such as “synthetic oils cause leaks”. The oil doesn’t CAUSE a leak, rather synthetic oil is able to pass through more easily due to the molecular arrangement. If you had a length of chain and held it by one end you could easily drop it down a small hole. If you were to take the same bit of chain and bunch it up into a ball, it would no longer fit into the same hole. It’s exactly the same principle just scaled up a billion times. All that being said, one oil type is not better or worse than the other. It just comes down to the engine and condition of the engine as to what is better to use.

Engine oil is now very sophisticated chemistry to match the high tech machining tolerances on today's engines. Engine oil and the other fluids are now "parts" specified by the manufacturer like any other part in the vehicle. You wouldn't put diesel fuel in a gas engine car and vice versa. You wouldn't put olive oil in your crankcase, nor transmission oil(fluid) or differential oil. It's the wrong part for that "application". Most new car engines today are "broken in" from the factory. Synthetic oil actually flows better for these tighter tolerance machines. Synthetic oil is more durable under the higher heat conditions in today's engines because the oil molecules in synthetic oils are more uniform vs. refined crude engine oil. Crude oil is a mixture of longer chain molecules and shorter chain molecules so over time and miles the shorter chain molecules burn off leaving an oil with different properties than when it was installed. In effect, the non-synthetic crude oil "wears out" and must be changed more frequently. Synthetic oils tend to remain more consistent and maintain their properties over longer mileage oil change intervals. That's one reason why the manufacturers recommend longer oil change intervals. Tighter tolerances in cylinder bores, piston rings, etc produce less blowby so the oil doesn't get as dirty via carbon build up in the oil system. Turbocharged gasoline or diesel engines especially with direct fuel injection actually require synthetic oil with "low ash" content to be used or the warranty will be voided. Gotta use the correct "part number" with the correct "specification". Other oils including ordinary "full synthetic" over time can damage the catalytic converters and can "coke up" the turbocharger bearings when the engine is shut off without letting the engine idle a while to cool down the turbocharger housing and oil within it. With low ash content synthetic oil, this apparently does not happen. When synthetic oils were first arriving on the market, it was advised not to use them in older engines. This wasn't because they would "create" leaks. It was because synthetic oils are usually thinner viscosity and would seep through gaps in older gaskets and seals on those older engines built with less precise tolerances. The older oils being more viscous would not find a way out through micro passages in those old cork and paper gaskets. Most gasket materials today are synthetic rubbers, etc and aren't even called gaskets. They're called seals. The synthetic oil does not escape unless the synthetic seal material shrinks, hardens or cracks necessitating seal replacement. Older engines should continue using refined crude oils, but definitely not newer technology engines. Read tye manual as to the SAE rating advised by the manufacturer. It's not hocus pocus. It's modern chemistry which y'all should've paid attention to in high school.

I’m here to tell ya 👈🏼‼️‼️‼️‼️ purchased a 2000 DODGE DURANGO in year 2000 I live up in the North East with temperature swings of about 90* summer to around 20-30* I’ve used MOBIL 1 since first oil change and changed every 3500-4500 mls with attention paid to the mileage. Turn to year 2023 and I’m still driving my DURANGO with 339,000 mls ! Still runs perfect! Been through 3-4 sets of brakes , two radiators a water pump and now on the 3rd set of tires ! And only 2 complete tune up’s all completed by myself excluding the tires. Driven to Fl. Twice and up to ski country every winter. The 4.7 engine doesn’t even have a tick ,knock, or even a sputter to this very day ! Mobil 1 10W30

My 2002 Volkswagen GTI (1.8 Turbo) just kicked over 319,000 miles on mobile1 synthetic 0W-40. Original bearings, valve train, everything.

I have run full synthetic oil on two Briggs twins since first oil change one has over two thousand hours one has nine hundred , oldest one puffs a little smoke on start up but uses no oil between fifty hour oil changes. I think the smoke is from fuel as the motor has a manual choke . I use synthetic for the heat rating what better to use on an air cooled motor.

I've been using 100% Synthetic Amsoil and all of my vehicles, mowers, and toys for over 16 years. All I can say is I love it because it's 25,000 miles or 1 year. So it is a win-win to me.

Buy a quality lawn tractor with a quality engine, use synthetic and run it forever

Standard oil doesn’t have the lubricity of synthetic oils so a new engine will not allow the pistons and piston rings to cut and seat. New engines are run on standard oil before they leave assembly plant that is the reason they state synthetic oil can be used immediately. Synthetic oils are vastly superior to standard oil. My background building engines 30 years. Not sure if still available or same formulation but the old Slick 50 additive will make engine seizure veritably impossible because of very high lubrocity.

After an insane amount of research on this subject - it is way more important to change your oil in any vehicle as appose to choice of oil used. Kohler may be an outlier for break in. New car/truck manuals/spec are calling for oil changes to be extended out to 10,000 or beyond. Oil companies like Mobile 1 have 15,000 mile changes on their extended performance jugs. Don't do it! Modern engines are designed for maximum mpg. They trash the oil much quicker with blow by and turbos. Change your oil when the "oil life percentage feature" in the dash says 50% life left. This is equivalent to around 4 to 5 thousand miles. Change your oil. It will save your turbos first and the engine right behind that. Change oil at 4 to 5 thousand max.

I build hot rods, engines and transmissions, do body work, painting and upholstery. I don't use synthetic oil for break-in's but after that I only use the best synthetic oil and that's Amsoil. Have used it since 1995, wouldn't use anything else.

Don't use synthetic oil. Oh, you can use synthetic oil. What He meant to say is don't use synthetic oil if you have a Kohler engine and not during the first 50 hours during break-in.

Comes factory in corvette vehicles around late 90’s early 2000’s and I’ve built many engines over the years and as long as you keep maintaining your engine properly it will last longer and never use synthetic oil in a new engine until you have minimum 10k miles because the piston rings won’t seat just goes to really show how much synthetic oil reduces wear