Agree 100% with your comments on 4wd vs 2wd. Also, in every vehicle I've ever driven, 65mph is the sweet spot of balance between fuel efficiency and speed. More than that and your mileage starts tanking.

Wind Resistance increases to the square of the increase in speed, so if you double your speed, you quadruple the wind resistance. There is a huge difference in wind resistance between 90km/h and 110km/h, especially in a 4WD with lots of things hanging off it.

" aerodynamics that your vehicle manufacturer spend millions of dollars on" Engineers at Landrover scratching their heads..

Cruise control saves me from speeding tickets which saves me money for fuel!

"Nah I own a Jeep, aerodynamics don't matter for them... it's already f**ked"

Ronnie your vids are legendary mate. You make dry topics interesting. A true talent.

Thank you will definitely be taking all of this into consideration as I build.

Mate thanks for the advice, very honest and informative. You are spot on about the 90km speed, I have tested it and its actually true. As usual, great work Ronny.

I like details and the way you present them. Keep on as I will probably deploy some of them on my newly bought 2009 Prado!

Best channel on KZfaq Ronny keep up the great content! Cheers from Canada

As a caravan owner I talked a mate with a camper trailer and Triton to stick with me at 90 for a trip. He saved over 6l of fuel per 100km rather than doing his normal 110-120kmh like he did before. He couldn't believee it. Even in my Pajero 3.2 did it means around 3lt per 100 difference when towing.

I have a Car and Driver feature on aerodynamics from the 80s and it found that a Land Rover Defender on the highway has the aerodynamics of a Volvo 760 towing another Volvo 760 in neutral on a rope. The best live axle 4x4s were all designed pre-aero. Ronnie is right about the 10 km/h as speed and energy required is an exponential function (ie more equals way more).

THANKS, VIDEO AND YOUR DETAIL ON 4 WD AS THERE LOT CAN DO TO SAVE FUEL COST WHEN ARE TRAVELING

When it came to mirrors, I was surprised it took you so long. Us mechanical engineers spend ages trying to make mirrors more aerodynamic as anything that juts out causes so much wind resistance...

Even an unladen roof rack added 10% extra fuel to my GQ Patrol when I had it in the 90s.

Great advice Ronnie. Love the videos and all the tips 'n' tricks. Now like you say in this video one of the biggest thing is how you drive. My mate and I both have 93' model Toyota Hilux, we recently did a Vic high country trip that totaled 1000Km. So same vehicle different driving styles. He used over the course of the trip 60L more fuel than me.

Great video Ronny. I will be building my truck and posting the build on my new channel starting this spring. I plan on a 38 gal fuel tank getting rid of the old 22 gal mid mount tank, I am running 265/75 R16 tires on it no need for extremely large tires. Plus I am fabing a steel military type bed for the truck which will be way lighter than the overly built flatbed that is on it. Being its petrol and the original engine is too underpowered for what its being set up for I am slightly increasing the size of the engine that will still bolt up safely to the factory gear box.

Agree with you regarding the cruise control issues. Especially when going up hills. However cruise control is a great addition on long boring flat roads. It allows that cramped up leg on the accelerator, to be shifted into a more comfortable position, after hours of driving. Perfect for outback driving.

Thank you Ronny

VEHICLE LIFT! This was the one thing that made a big difference to my diesel economy. Effectively a bigger frontal surface area, where the underside of the car is not even remotely aerodynamically efficient.

Great tips, and couldn't be more right. Speed has the biggest impact on fuel economy since drag goes up as the square of velocity. An increase in speed from 90k/hr to 110k/hr is a 50% increase in the amount of drag. Couple of other tips: On vehicles that have locking hubs, unlocking them in 2wd if you won't be needing 4wd will help. Oil weight can make a difference in the internal friction of the engine - use what the manufacturer recommends for your temperature. if you are in colder temperatures, changing to the lower weight oil can help with economy. Also, if you have a petrol car, replacing a faulty o2 sensor can make a big difference as well.

Love these videos Ronny

Some great tips there. Thanks Ronney.. I drive a old Jeep Cherokee, Does not matter what I am doing it just gets poor gas mileage. If I am pulling 5000lbs down the highway or driving to the mall it gets the same mileage.... See you on the trails, George.

I have a Discovery 1 TDI 300 engine. Equipped with bullbar ,winch, roofrack,rooftop tent, mud terrain tyres & all camping gear loaded to survive weeks of travel (2 adults & 2 kids ). I have done trips traveling at the posted speed limit & returned economy figures of 10.5L /100Km. Only used 90L going from Birdsville to Mt Dare. I haven't seen any 79 Cruisers get even close to this . One feature I added was a engine saver & the digital cylinder head temp let you see when you were driving it to hard on long hills or with headwinds.

I agree with everything you say ronnie apart form the recommending of a landcruiser

i got a 4x4 recently, and went up to selwyn snow feild NSW and on my way back down i hit black ice doing 20km or less, and slid into the barrier going down hill, luckily I was slow and just tapped it, bullbar helped me going round corner, stayed on my side of road tho

newer model 79s got regeared to lower the rpm's on the 79 id look into that change not saying you are wrong just wanted to let you know bud. love ya vids keep up the good work

Great video

It’s crazy how much fuel you save driving between 90 - 100. I traveled around Aus in my hilux and the difference between cruising at 90 - 100 and doing 110 - 120 is about 100ks extra out of a tank

Great Vid once again, though I’d like to say that these days many “modern” petrol engines can be as economical as many diesels .

Hey Ronny another comparassion you should do is ute vs wagon. Keep up the great work.

Nice one Ronny

I added a light bar with 4 6” Lights to my stock ‘15 JKUWW and went from getting 19-20mpg on highway road trips to 15-16mpg... which is actually worse than my city driving mpg. I was pretty surprised at that difference.

use momentum wisely

victoria, i need the bash bars and rock sliders.. and roof rack is essential, lucky they make them with the wind thingo now.

I love the point brought out on 2W vs 4W when hitting gravel. I've always switched right away to 4H, and I've always got the comment "why are you switching so early you are losing another 10/mi per gallon."

The bit about downshifting to climb a hill depends a lot on what sort of engine we’re looking at, NA gas engines typically are at their most thermodynamically efficient at low RPMs (above idle!) with a wide open throttle. Things get more complicated when you add forced induction, gas engines need to richen up to avoid detonation, diesels often need to richen to keep the turbo from overheating.

Thanks, man!

Revs also play a huge part in fuel on highway, definatly better to sit around 90 instead of 110

Your argument is absolutely correct. Chip tuning sometimes let the engine do the same work in a "shorter time" without making it overheat. The mods should not include turbo/superchargers. These are fuel & engine killer unless you upgrade your pistons and crankshaft(Which are costy and unnecessary)

I got 2 toyota trucks 4runner (hilux surf 5VZFE) and a 100 series cruiser V8 gasoline. I replaced coil packs with all OEM and Denso TT spark plugs on cruiser and noticed an improvement in MPG. Currently at 230K miles and I get 7.11 Km per liter at 115 KmpH with cruise on. The rake at the rear end (rear end of the body 2-3 inches taller than the front: the factory setting) seems to improve the gas mileage as I experience with the 4runner. New sway bar bushings will also contribute to some MPG because it tries to keep the truck steady on the road helping to maintain good aerodynamic characteristics. I installed a bull bar on a hilux 106 diesel and right after that I noticed I cannot roll after a stop in the 2nd gear without revving the engine. Without the bullbar I can proceed from a stop in the 2nd gear at idle. OEM brake pads have contributed to an increase in MPG. OEM air filter will surely improve the MPG. I witnessed all these in my trucks and wanted to share it with others. These are in addition to what Ronny said. Please make more videos....

One thing you didn't mention mate was lift kits, up to 50 mm is fine but more than that alters the aerodynamics of a vehicle and seriously increases fuel consumption. All the rest I agree whole heartedly with especially cruise control.

Greast video, Ronny! Maybe you can tell a bit about the effect of snorkels?

I've added full barwork, a fully loaded 1200 canopy which overhangs the sides and top, slimline roof bars plus much more on a V6 N60 and my fuel consumption has not really changed from around 12-14L depending on situation. Whereas I constantly see people on 33 inch tyres getting 15+ consistently without significant other mods. Bigger tyres definitely chunks fuel consumption more than anything else.

Every part of every vehicle is a compromise, and understanding the compromises are crucial to improving fuel consumption.

If I am driving on freeway/highway, I will cruise at about 90km/h - this speed, even with roof top tent, seems to be the sweet spot - any faster and the aerodynamics (or lack of!) really hit the fuel consumption hard. My RTT is worse than many, because my rack is on 11" legs to clear the roof hump & factory rails on my Discovery 2. Oh, and it's V8 Auto. Last trip I did, fully set up for camping weekend, I averaged around 18L/100km. Very happy with that!

Loving your vids ronny! Ive been searching for a 4runner here in europe for 4 months now. They are really hard to come by with only 70 being sold st the moment. Trying to get the 3l diesel. Watching your videos as prep 🚀

PREACH! Love the only add the extra weight if its necessary! I found that out the hard way, and the expensive way lol

On bitumen, imo, cruise control is brilliant as it greatly reduces fatigue over long distance. On gravel, I don't use cruise control as it becomes a safety issue (once again, imo) due to a potential loss of control. I've bought a diesel 4wd and it has a long range tank, I have a sedate driving style and I'm getting about 8-8.5 litres per 100km, and therefore about 1600km from the tank depending on load and driving conditions.

I actually got my EPA rated highway mileage on my 80 the other day, the trick was driving 55 mph (90kph). 15.3 mpg sounds poor (it is) but given 33 inch tires, roof rack, 4.56 gears and 300,000 mile engine...I can handle it.

One more time you put everything together in a nice way which is very useful for most of users. I also have to submit that it is the first time that I hear from someone else what I always say about cruise control. I Totally agree with that. Cruise control is just for putting your legs in a relaxing position while traveling and that's all. What I wanted to here and you didn't mention is if snorkel does effect in fuel economy. There are a lot of different opinions. So what's yours?

Ahoy Ronny, As the previous post explained, aerodynamic drag is, amongst other factors, proportional to frontal area, and the velocity squared! Frontal area, road friction and other factors add up of course, but not as much as higher velocity. Driving the desert tracks very slowly, velocity and frontal area have small impact, other factors drive your economy. Driving on bitumen highways at 110Km+ your velocity (& your frontal cross section) will drive your economy. Hope this helps. PS. The Drag coefficient also grows as you get to Mach 1, and them drops off again! Best to travel at much less than Mach 1, or over Mach 2, ideally at high altitude.

One thing often not considered is that rotational mass takes about three times more force to accelerate than static weight. For example, if you upgrade stock tyres to 35's you are easily adding 15 kg per wheel. This 60kg (15*4) rotational mass increase is therefore actually equivalent to having an extra 180kg on the vehicle

Love to see some figures logged out of the canbus on a modded 70' like yours vs a stock 70 over a few trips.

Hi Ronny, Great vids mate. can you do a vid on setting up a second fuel tank? and any chance of a link to where to get the 12v power supply module? cheers

Thanks Ronny. Would like to hear your experience with the snorkel in relation to fuel efficiency. I am considering one for my petrol vehicle, but have heard very mixed reviews about it's effect on fuel consumption.

Also rpm difference between 90 and 110, I have a 2.1l and it makes a really really big difference, even 100 to 110 it means staying at 2500 and 3000 rpm. Big difference in fuel

I didn't buy my 1995 Jeep XJ for its absolutely terrible fuel economy. And I didn't put larger tires on it for better fuel economy. Nor the heavy front winch bumper, Rock Sliders or Rear Bumper either, but living here in the Western US, we have large distances to travel to get to the best spots to wheel. Lots of wide open spaces in between the rocky, fun bits. So I do what i can to conserve as much fuel for the off-roading parts of the journey by simply driving a bit slower. And yes, if you don't need the extra body armor, then don't put it on your vehicle. Simple enough advice, but you see a lot of people here in America doing just that. Hanging all sorts of crap on their trucks to just crawl around the local shopping malls. LOL! Anyhow, thanks for the tips from someone who has done it and seen it! Keep it up!

my rooftop tent on a 2017 hilux @ 110/120km/h has fuel consumption of 14L per 100km, if you are driving without a rooftop tent @ 160km/h it uses 12L per 100km. crazy the difference a bit of wind resistance makes, the worst thing by far is the wind noise though

I replaced the stock 30" tires with 32" Michelin XZ's (heavy, but not wide military tires) on my BJ 60 and went from 25 Imp. mpg to 27 Imp. mpg on the highway. Max. speed was still slow. Off-road hill climbing suffered.

Doubling the speed makes the vehicle encounter twice as much air traveling twice as fast causing drag to quadruple os with a small increase in speed the drag goes upX4 .

Love the rhodesian ridgeback of yours, a bit chunky, have him more active and feed him better food! Great vid as usual, keep it going!

Jeep Rubicon Wranglers are geared for 35 inch tires also.

Happy fathers day Ronny

Cruise control makes a noticeable improvement to fuel economy in my Defender. It also makes long hauls on the road a lot more relaxing.

From driving HMMWVs in the service, I agree with going 4x4 on gravel...

Fun fact: A G 63 at 250km/h consumes over 60l/100km.

OK for you young fellas not to use cruise control to save fuel, but it is very effective in reducing driver fatigue!

Ronnie didn’t mention the difference in MT-AT tires in weight and rolling resistance in the same size my MT load E tires are 12-18 pounds heavier than a AT and 20+ heavier than a street tire all same size. Great video Ron, it seems to me like every single thing I did to my truck cost 1 mpg per item.

Another point..... if you're driving a turbo charged rig (gas or diesel), try to determine the RPM at which the turbo starts really going to work. Keep the RPMs below that and you will save a TON of fuel. On my 7.3L turbo diesel, 1850-1900 rpm and less consumes substantially less than 2000 plus rpm because at 2000 plus the turbo is stuffing enough air into the engine that the fuel system can stuff a whole lot more fuel into each cylinder full of air. Turbo's are great for power when you need it and for maintaining power as you climb into higher altitudes (by maintaining fuel air loading in the cylinder) but they can destroy fuel economy as well.

Going back to the tailgating point, as proven in NASCAR or on mythbusters, you have to be so close to the vehicle ahead, that you are unable to stop, your reaction time disappears. In the event that lead vehicle crashes, you'll be the first to know. As you pointed out, don't tailgate a semi (or road train for you down under), in the event that trailer has a blowout, that tire carcass will be in your lap before you brake. Seen it happen.

I agree with most of what you say, except I have found driving to revs rather than speed gives me best economy, I have a Pajero NT 2011, when towing a heavy trailer I try as hard as possible to drive at about 1900 revs and although this can be frustrating at times mostly I find I am doing speeds in excess of 90 klm often over 100, however the caveat on that is of course a head wind :-). I have a lot of gear on board and a lot of weight towing and on average 6.5 klm to ltr. roof rack 4 jerry cans not always full of fuel max tracks winch roobar metal rear bumper draws and using the under seat storage for gear as well, spare tyre not a rim, 116 ltr of water inside rear seats removed snorkel catch can chip tuned to economy. Anyway just my two bobs worth :-)

I am just screwed all around. 2.8 gas (petrol) in a Jeep Cherokee XJ with 4.56 gears and no OD. Engine is WAY too small, and it gets a whopping 10 MPG, (23.5 l/100km). However, it won't use a full tank during a full weekend of off roading.

On a diesel, get a water methanol injection system, more power, more economy. It has shown to be very effective. Many use them to reduce exhaust temperatures for towing. About the power, they add about 25% more power, or 10-15HP per Litre, no tuning needed.

Great video (as usual). Couple of thoughts if I may indulge . . . I think all 4wd ers should understand the curves of their torque and power output (enginewise) that way, like you said, you can choose when to downchange rather than letting motors labour. Also it can help on upchanging to know if you are heading into a sweetspot where torque and power are delivered easilly as this saves fuel. The 90kmh concept is very true I find if towing (I have a Pajero Sport 2019 GLS and tow a euro aerodynamic 1700kg Atm caravan and achieve 12 to 14 litres per 100km depending on altitude and wind direction. Keep up the great work that you do. 2 questions please, would adding a snorkel to my 4wd help with economy? Can an oil catchcan be legally fitted to my vehicle as it has a DPF? Your opinion would be appreciated.

Don't need a bigger engine to tow I think. My 130 Td5 with a 2.5 litre 5 cylinder diesel will probably use less fuel than a V8 cruiser while towing, or in any other application. I once towed a smaller trailer with my 4.2 petrol V8 Range Rover classic auto and got 13 litres per 100km on a 500 kilometre trip and that was with a Defender roof strapped to some roof bars as well! The speed was never higher than 80 km/h as it is the speed limit while towing in Sweden. That makes for safe and fuel efficient towing!

A snorkel and even upgraded exhaust can help your fuel economy somewhat

Maintainace... Very Big Point... I Drive an old Mercedes with a half a Million Kilometer in the clock.... Changed the injectors and got from 12,5 L down top 8,9L

Worth watching, fuel prices going up

tell me about it, I drive daily a 97 supercharged 4.5 petrol land cruiser with rack RTT barwork on 37s. Lol you have to be willing.

I like the video a lot!!! What is the off set on your rims?

I usually do 130km/h down a steep hill and nothing up the hills, saves heaps of fuel.

I remeber the UK road research centre calculated a roof rack on a Landrover added 20% to fuel consumption at 100kph!!

The biggest hit I had to my MPG, over the RTT, Drawers, fridge, dual battery setup was larger heavier tires.

New 2012 amaroc drive home 1100ks arb canopy -150 ks hwytyres to at3 coopers approx ~ 50 3 bar roof rack ~ 80 front canopy bar removed front cab bar removable -70 ks arb Sahara bar -50 at best 800ks /80tank perhaps it’s done 48000ks

On a long flat run I use my GQ Patrol's hand throttle as the cruise control. Set it at 90km/h on the flat, if it varies a little that's ok. If you hit a big hill, put the foot on the throttle. Only bad thing is you need to remember to disengage the hand throttle before slowing down or changing gears. Agree with the 90km/h. Car drives nicer, much more relaxed. Doesn't jump around so much with the 4" lift, less tiring. There's no race, just wind up the music. And getting down around 10L/100km with 10psi on a TD42 puts a smile on the face.. It just purrs. And 1200+km from a 130 Lt tank isn't bad either.

When you say Cruise Control do you mean on or off road. I know that when I started using my cruise control on road the fuel saving was quite considerable. I know people will say that's a driver issue but I want to concentrate on other things when I drive like avoiding idiots. As far as using CC off road, well I simply don't use it.

GREAT POINT on the chip tuning. It's a human nature issue. Those who are going to spend for a tune are the exact types (we're talking groups and stats here not any one individual) who are going to romp the fuel pedal, show off, etc. and undermine any fuel savings. The roof tent and/or gobs of gear on a rack WILL kill fuel economy when at speed but when off road at slower speeds (where wind resistance is minimized) it is less of a concern. Wind resistance is a logarithmic function of speed (i.e. resistance increases exponentially -- more per MPH with each increase in MPH).....NOTE: so is the kinetic energy you will experience in a crash so lower speeds are exponentially safer..... This physics limitation completely explains your final point about speed and fuel economy as well as the big chunks in the wind portions. Wind resistance increases exponentially with speed. Tire size. With bigger tires and wheels you increase friction but you also increase "rotational mass". An engineering term used to calculate how much inertia must be overcome to change the rotational speed. The higher the rotational mass the more energy (i.e. fuel) is required to make it start turning or turn faster (accelerate) as well as requiring more energy dissipation (i.e. brake heat/wear) to reduce rotational speed. While the braking issue doesn't decrease fuel economy, the increased energy required to overcome the increased rotation mass does affect fuel economy. AND as an added bonus, taller tires present a larger aerodynamic "plate" to further help reduce fuel economy. Just some thoughts from a retired US Marine, mechanic, pilot, and physics bum

5.0L DI V8 AJ133 here, Best not to pay attention to the price on the pump. ;)

What make and model is that small trailer? And do you have a video where you show more closely that "bed" you have, it looks so sweet I'm considering of ditching my stock bed and building one like that!

Hi Ronnie - can you consider doing a video explaining how to use the explore mode on Hema HX1?

I’m suddenly realising that maybe I should wait until I actually need all the fancy things before I do anything to my ranger. Right now, I’m only legally able to go to work and the supermarket and right now, I could manage with a Prius

What's your opinion on the Columbus Carbon Fiber RTT? Not for fuel but just as a RTT option. I'm really liking the look of it for its slim size, light weight and super simple fast setup (one catch and push it open... done).

1 thing you didn't add was the correct diff ratio it is totally when you tow something oppose to just having the weight in the back.. as for bar work i believe in full exoskeleton roll cages for my vehicles because it is 1 of the biggest safety features you can as from the late 80's to early 90's vehicle manufacturers to save weight started to aluminium as the building constract as such taking the texile strength out of the vehicles as such vehicles of today generally don't last in a roll over.. this option also gives you a recovery point you can attach too.. most nomads that I come across have stuff all clue on how to tow or pack a caravan let alone what their legal speed limit is given the weight they are towing... Especially if there prime towing experience is a 6x4 trailer full of garden waste... tail and head winds do effect fuel economy I suspect with the addition of DEF on vehicles you likely waste more fuel wh its use.. the original spec for land cruisers in the early to mid 80's was 5 ton, average weight today is 2.5-3 ton back then you had 3 engine options availacle v6 petrol, straight 6 diesel or v8 diesel and turbos or super chargers were the added optionals.. though you would usually opt for diesel because it had an engine break system.. with 13 tons on the road between caravan and vehicle you needed that stopping power in the cruiser.. this weight basis is based on towing a 30-45 foot caravan my opinion on petrol 4x4's soccer parent or work site type application looking the part though not really designed for true off road use..

throttle position is always the biggest cost of fuel think about it you can be at red line at light throttle or wot....in every truck and car iv had i got best fuel econamy if i use light throttle and just let the gearing move me down the road

weight and speed............eat up fuel. Even worse is wind........if its windy back off to 80km/hr or stop and wait for the wind to drop. In some parts of Australia, the wind can be very bad in open country and really eats up fuel. Excellent advice.........dont tailgate heavy trucks day or night........truckies hate it and will even pull up to make cars pass.........I know I did. Also a lot of diesel vehicles getting around that have some age on them blow smoke like crazy.........thats wasted fuel, usually just the injectors need a service.

I drive a Ford V-10 - fuel consumption is a Captain Obvious.Anyway, on your current "remote desert" video series you have four very similar vehicles. Two 79 single cabs, two 79 double cabs. Give us a real world comparison of fuel consumption between those four vehicle and your take on why the worse is the worse and why the best is the best.Thanks.

I've hear the 4x4 methodology presented differently. Both my grandfather and his father always said the 4wd system was made to get you out of trouble not into it, and that you only engage it for technical challenges, slippery terrain, hill climbs, etc. In my own experience, a graded gravel road doesn't require 4wd at all unless you want to drive fast, or drive in inclement weather. Outside of those cases the 4wd system has no impact at all on vehicle safety.

I like your Rhodesian Ridge Dogga

My radiator is leaking in my 2000 Chevy Silverado 1500 and holy shittttt my gas mileage is bad. When I got my truck I got around 350 mpg on a full tank of gas about 21 gallons of gas not bad now I'm getting about 250 ish.