Grenadier, Defender, Patrol, LC300, Part 2: the Slow Race & Hill Descents Explained

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L2SFBC - Robert Pepper - auto journo

7 ай бұрын

#Grenadier #LC300 #Defender #Patrol #hilldescent #crawlratio
Which vehicle can descend the slowest? What is engine braking and why is it important? Demonstrated with an RC model, of course, and then see Grenadier, Defender, Patrol, LC300 battle it out...slowly! Also explain what a crawl ratio is.
Part 1 Intro, suspension, climbs • 4X4 Tourers Offroad: G...
Part 2 Slow Race; crawl ratios, descents • Grenadier vs Patrol vs...
Part 3 Slippery Climb • Grenadier, Defender, P...
Part 4 Clearance Climb • Grenadier vs Patrol vs...
Part 5 Momentum • Grenadier vs Patrol vs...
Part 6 The C/D Problem on Hills • The Centre Diff On Hil...
Part 7 Lockers vs BTC • 4X4 Tourers Offroad: G...
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Пікірлер: 86

@Land_Raver 7 ай бұрын

The most looked over physics principles by 4wd'ers is static friction coefficient vs kinetic friction coefficient. Your demonstration in the beginning illustrated it perfectly.

@L2SFBC 7 ай бұрын

Thanks...I generally avoid technical terms which is why I didn't mention it.

@adampoll4977 7 ай бұрын

Always great, informative content.

@jameshoward9700 7 ай бұрын

Such an important factor off road - well illustrated. Too often we get locked on to axle articulation and big wheels, but hill descent is crucial to safety. Having just put down a deposit on the Grenadier, I’m quite smug too!

@AquaMarine1000 7 ай бұрын

A good friend of mine has his Grenadier in production. I'll be checking it out after it arrives early in the new year. Cheers

@FickleHead 7 ай бұрын

Tested this exact test out 2 weekends ago in my Grenny and was very impressed!

@gadgetphilosophy8290 7 ай бұрын

Brilliant demo. I found that in the old days. The best and safest way down any muddy slope was low range 1st. Both diffs locks. Idle downs and ride the brakes to slow you down. Because both lockers were on and it was manual no wheels could lock up.( or you’d stall) It was amazing. Better than any HDC.

@L2SFBC 7 ай бұрын

Low first can be too low sometimes. I have a video on lockers too, definitely consider using them downhill.

@mikewho9964 7 ай бұрын

Great explanation followed by actual real life demonstrations - thanks

@L2SFBC 7 ай бұрын

Glad you enjoyed it!

@No-thing-ness 7 ай бұрын

I love that the conditions are not dry

@L2SFBC 7 ай бұрын

They are dry

@jamiegibson8212 7 ай бұрын

Another great comparison - might have been interesting to see how the various HDC systems compare even though I very rarely use mine. Maybe for a future part?

@rhetth-s8082 7 ай бұрын

Great video. Focused on what matters. The different torque converters in the vehicles probably have some difference in slip ratio, but what happens in a simple test like this is what counts. These days some people focus on downhill cruise control but its just complex and blind braking, and brakes overheat.

@bmonck5110 7 ай бұрын

Fascinating thanks

@baronvonteuchter1412 7 ай бұрын

Great series of videos. I’d love to see a comparison test of MT v AT on, say, the grenadier.

@briantoner5247 7 ай бұрын

Very nice demo.

@L2SFBC 7 ай бұрын

Glad you liked it!

@Captain-Donut 7 ай бұрын

❤️🙏 Love from Scotland 🙏❤️

@sergeantschlumpf6368 7 ай бұрын

1:00 2:32 lovely demonstration.

@nnoddy8161 7 ай бұрын

The forgotten art of cadence braking. Could not help but laugh at the 'JLR' reference!

@L2SFBC 7 ай бұрын

No need for it!

@kirovfactory 7 ай бұрын

great vid as usual. but i believe one important factor you left out is the factory transmission setting if not a manual. The efficiency of transmission in descent aka "back dragging" is largely variable by varying the transmission control, doing funky hydraulic path switching stuff. manufacturers have to tell the transmission to largely quit "back dragging" in normal driving condition, otherwise a car would be funny to drive when it can't coast at all. sometimes they increase it after sensing a deliberate downshift, predicting that you want engine brake.

@ianscorey5293 7 ай бұрын

Interesting video…… but boys and their toys!!!! Regards Ian 👨‍🎤🇳🇿👍

@leftcoastoverland8750 7 ай бұрын

And the grenadier proves best in class again!

@L2SFBC 7 ай бұрын

it wasn't before..but this time a clear win!

@scandinavia6271 7 ай бұрын

Which is quite funny since i have seen tests on KZfaq stating the Grenadier Hill decent is Way too fast..🧐

@pauls4708 7 ай бұрын

cyclists use a gear ratio thing calld gear inches .If i remember correctly that allows for the actual diameter of the wheels. I am sure there is a way to express the comparable crawl ratio of modified to ummodified but its not comprable thing ..Thts is a impressive crawl ratio for the grenadier,i was wondering what it was.Interesting that the JLR speed seemed to be relatd to something else other than absolute crawl ratio

@blikkiesblignaut6999 7 ай бұрын

Excellent explanation. Please do a test with the Granadier to show the same , but with HDC against lockers on a steep downhill with ruts where 2 wheels are in the air. I put my money on lockers.

@L2SFBC 7 ай бұрын

I've done that with my Ranger, same effect will be with Grenadier. Video linked in that one.

@brianmaclennan561 7 ай бұрын

Was waiting for the second run with hill decent on....

@L2SFBC 7 ай бұрын

HDC works better with a good crawl ratio

@scandinavia6271 7 ай бұрын

@@L2SFBC Maybe so - but some tests point to the Grenadier hill decent being too fast?.. Why didn’t you just test the HDCs in the vehicles?

@landrover1155 7 ай бұрын

If HDC is well calibrated it adds nicely to good low range gearing by pulsing brakes but not allowing wheel lock up. The Discovery 2 manual V8 in low range was excellent down steep descents but with HDC on it would only occasionally engage (as 1:1 was so low and slow) and was always helpful. Cheers

@alexwbakker 7 ай бұрын

One thing I would really love you to cover would be the impact on side-hill performance with bigger tires. When I test drove the Grenadier, i was able to get it on a 36 degree side hill and it didn't roll over, which I found impressive. They quoted me 45 degrees as the design spec. However, where I am, I'd love to run a 33 or 34" tire for additional clearance, and don't have a good practical sense of what that does to the roll-over angles.

@overlandready 7 ай бұрын

simple, the taller the ytre, the higher the centre of gravity so the less stable on a side slope, which is another reason not to go big tyres. I would agree a comparison on what actual degree effect it makes would be good, but not sure many people will want their vehicle tipped over many times to work it out.

@alexwbakker 7 ай бұрын

@@overlandready indeed. It is simple to say that taller is worse for CoG, but it is not simple to show what the degree of impact is. My suspicion is that the there is a range where the impact is not very big, and then a "tipping point" where additional height is more problematic. Obviously, unimogs on portal axles don't tip over easily, so it is manageable. I'd love to see the testing.

@davidabcab 7 ай бұрын

Not a straight forward case of COG getting higher. Small factor that does become an advantage is the heavier rubber. Unsprung weight is your friend on side slopes (depending on how floppy your suspension is though). From my 29" standard wheels to my 33's I have on now, there is easy a 15kg difference per wheel. But this demonstration is spot on. My old Nissan Hardbody with dual TC has a final drive of around 90 I think, and the control you get from that is just amazing both up hill and downhill. I love my crawler gears.

@L2SFBC 7 ай бұрын

36 degrees is not an impressive side-slope performance. Talk to me when you're at 45. I'm not going to test that as it's a bit pointless and super high risk. A slightly taller tyre won't make any real difference, your backside will call it off long before the car rolls. Sideslops are the #1 way to demonstrate a 4x4 and scare people.

@angeloudy 7 ай бұрын

If you increase it to 33", it only increase the height by 1.5cm, which can be compensated by increasing the wheel track slightly, like reducing the wheel offset a little bit

@arefeshghi 7 ай бұрын

I like these videos as they contain useful scientific information. Do you have an offroading group / club or something like that by any chance?

@L2SFBC 7 ай бұрын

my Patreon

@villadazzler 7 ай бұрын

Nice video! Do you mind listing the crawl ratios for each vehicle please.

@L2SFBC 7 ай бұрын

They are written on screen in the video...that's why it's nice

@villadazzler 7 ай бұрын

@L2SFBC sorry, I missed that the first time! 🤦‍♂️ Thanks!

@robinireland810 7 ай бұрын

Finally! I can win a race by being the slowest! My life is complete. I’d like to thank Ineos for making this happen, and my parents for leaving me enough inheritance to train for such an important event……🏅

@RoamingRooma 7 ай бұрын

Nice educational vid again. What will be the Crawl ration for 79 series

@dethak 7 ай бұрын

43.95:1. But, being manual helps down hill.

@RoamingRooma 7 ай бұрын

@@dethak Gotta new one on order. Thanks Rob

@Pandora882 7 ай бұрын

In the Petrol Grenadier at 750 RPM with a 53.81 crawl ratio and 17inch wheels the speed is 2.04KMPH (Ineos figures)

@scandinavia6271 7 ай бұрын

Really good video - again!👍 One question; Why didn’t you just check the HDC in the vehicles? (to be fair - you were in fact going “down hill” / that’s what HDC is made for..)

@L2SFBC 7 ай бұрын

Because HDC is more important. HDC brakes each wheel..and I showed what happens when you brake a wheel. Keeping them rotating is better.

@cue03 7 ай бұрын

Thanks for video. How did you find the transfer case reduction? I can’t seem to find that call out on any spec sheet. Maybe I am not looking for the right line item. The other 2 numbers needed to calculate crawl ratio is generally available on the spec sheets for just about any off-roader/soft-roader.

@Chrisamic 7 ай бұрын

For what vehicle? We can't help you if we don't know what vehicle we are looking for. Some manufacturers will give a both high and low range ratios plus the diff ratio, some will just give gearbox, diff, and transfer case. The typical ratio for the transfer case is 1:2 (half) however it does pay to check the specs. Manuals and automatics will quite often (always) have different transmission setups so that is important information too.

@overlandready 7 ай бұрын

@@Chrisamic being pedantic, but half is 2:1 double is 1:2. 😀 Yep agreed, vehicle and engine, gearbox, options can all make a differnce.

@L2SFBC 7 ай бұрын

It's sometimes on the specs sheets, other times you have to ask the PR people for it...which tends to be another "what is this question and why on earth is it important, we've talked about the car's muscular stance and heritage, what else does he need"

@davidabcab 7 ай бұрын

Nice demo, but how do you factor in wheel size to your final drive gear ratio? We all seem to end the calculation at the diff ratio. I have calculated my wheel speed and worked that out to km/h for reference. 29's gave me 1.21km/h and 33's give me 1.38km/h at 800 RPM 1st gear with dual LR TC's. I can't get a simple way to work that to part of the gear ratio calculation though. All I know it is nice and slow, but your torque multiplication can break things in a hurry if you are not careful.

@L2SFBC 7 ай бұрын

The crawl ratio only looks at the gears, it doesn't factor in wheel diameter. I should maybe have added on to that the effect of wheel diameter...maybe I will in the commentary video that'll follow this one.

@GlenRoberts-xy1vd 7 ай бұрын

Tires do make the difference between driving and winching . Aggressive tread patterns, for greasy Muddy surfaces and slushy surfaces for higher elevations ( snow ) ideally tests should be a Year long requirement. Four Countries as the Golden standard . Australia, South America The US and Canada .

@r1chardarcher 7 ай бұрын

My 105 Series Petrol manual is lovely downhill in first gear. I think it’s a 42:1, but no torque converter slip. What’s your opinion on how these four went with keeping the engine revs low and low torque converter slip?

@L2SFBC 7 ай бұрын

Manual has historically been better for descents, but no longer.

@Davidsmith-mc2no 7 ай бұрын

Which of them has hill decent control and would that have help any of them go slower

@L2SFBC 7 ай бұрын

All do..and yes it would except maybe Grenadier!

@Roar. 4 ай бұрын

Weird to see the Defender descending that fast. You can manage the descent speed, so was this set correctly?

@environmentalvoicesAU 7 ай бұрын

So while I tried to understand the craw ratio, it seemed to have very little real life impact on the various vehicle’s performance? Or did I miss something?

@L2SFBC 7 ай бұрын

It's one factor of several. The Grenadier has the best crawl ratio and did the best. Defender under-performed a bit. So you didn't miss anything!

@villadazzler 7 ай бұрын

Something is not right with that Defender. I have a D250 and at 3 tonne, it is far slower on descent in 1L than the new Patrol, Prado, Pajero, LC200 to the point I keep falling behind in the convoy. 😂 Can't comment on the TrailMaster or 300 as yet no one in our club owns one, but this is interesting.

@L2SFBC 7 ай бұрын

The Defender had to do two runs as on the first HDC came on when a TR mode was switched and the driver didn't realise until he set off. Otherwise it was locked into 1st low like the others. However, the TR mode shouldn't make any difference to engine braking...but who knows. We didn't test multiple TR modes.

@davidabcab 7 ай бұрын

@@L2SFBC Not knowing much about these modern vehicles, which are diesel and which are petrol? Also not sure of the modern diesel's setups, but in the old days, diesels were not really up for big engine breaking as they did not have a throttle body like petrol engines have. So a diesel would only rely on compression, where a petrol would have the added benefit of the air supply actually cutting off. Cut the supply to a diesel and your engine breaking is way better.

@L2SFBC 7 ай бұрын

All diesel except Patrol which has no diesel option. Grenadier has a petrol version as does LC300 and Defender.

@operation4wheelz 7 ай бұрын

Can I just randomly show up with the Rubi ? Like, you know everyone wants to see it

@L2SFBC 7 ай бұрын

too late...

@AD28197 7 ай бұрын

I'm surprised the LC300 came in 2nd as it has the lowest crawl ratio

@Chrisamic 7 ай бұрын

It's only 2 1/2 tonnes, so not so much weight pushing it down the hill compared to the Nissan. The biggest surprise is actually the defender. The same weight as the Toyota and a lower ratio, it should not have got to the bottom so quickly. There's something not quite right about the set up with that one. Either the diff ratio is different from advertised or LandRover are putting more fuel into it at idle.

@markelliott6105 7 ай бұрын

If the Grenadier went any slower the Start/Stop would have engaged! 😂

@L2SFBC 7 ай бұрын

Yes, I was surprised too at the Defender, disappointed with it. I suppose JLR will say "well use HDC"...going to disagree there. Time was that you could never beat a Defender in a slow race..

@villadazzler 7 ай бұрын

I don’t know about the setup on the Defender in your test, but my MY21 D250 is painfully slow on descent in 1L, and it's over 3 tonne on the trail. MUCH slower than your clip. I am on 18" steelies with 33" tyres. Could this be a factor?

@peopleschamp7258 7 ай бұрын

@villadazzler Robert pointed out in the notes thT he had to do the L663 twice because the HDC kicked on. He wanted to show it without hdc. All o tem could have had the hdc on and based on the gear ratio, one would expect similar results just slower.

@davidmilledge221 7 ай бұрын

They probably all automatics them , a manual gearbox put in the lowest gear , crawler gear and send it bloody simple , dont need all that electronic driver asist crap no good one day out there and you get electronic gremlins or a fancy abs senor packs up , fancy blokey women stuff 😅

@L2SFBC 7 ай бұрын

Yes all automatics. Driven by men who don't tie their masculinity to their car.