Steep Descents using reverse gear

Submitted: Friday, Feb 03, 2006 at 10:46
ThreadID: 30376 Views:4838 Replies:15 FollowUps:42
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In the Feb issue of 4WD monthly in the article on the Patrol family, the article suggests to use Reverse gear in the auto 3L diesel for steep descents, but not for long periods. I have never thought to do this. My previous 4WD was an auto Jackeroo petrol and I have negotiated some pretty steep descents and found that first in low range and a bit of brakes was always sufficient. Has anyone used the reverse gear method before with auto gear boxes? If so what sort of distance & what is the damage factor?
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Reply By: Rob from Cairns Offroad Training & Tours - Friday, Feb 03, 2006 at 11:03

Friday, Feb 03, 2006 at 11:03
As a traineri hear a lot of different methods for steep hill descents in autos. Dave you have the right idea, first gear low range and gentle braking to control speed. I hear about the drive thru the brakes method with left foot braking, why complicate the issue an auto wont stall so why drive thru brakes? Reverse going forward down a hill WHY? Cant be good for the tranny Brakes are there to contol momentum and speed use them gently and wisely on steep slope so as not to lock wheels and loose steering control. I have an auto and wouldn't even consider putting ih reverse to go forward down a steep slope. Cheers Rob
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Follow Up By: Leroy - Friday, Feb 03, 2006 at 14:10

Friday, Feb 03, 2006 at 14:10
the reason for dirving throught the brakes is to ensure that all wheels are being driven and as a result are turning and helping traction. for example. If you go down a steep hill in the wet and apply the brake then you will no doubt lock up a wheel and it will skid. This is also because the wheels aren't being 'driven'. If you let say keep your engine at 1200 rpm and then regulate your speed with the brake pedal then all wheels are being driven which in turns helps prevent wheels locking up and skidding out of control down the hill.

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Follow Up By: Rob from Cairns Offroad Training & Tours - Friday, Feb 03, 2006 at 15:54

Friday, Feb 03, 2006 at 15:54
I have some VERY steep hills on my training tracks outside of Kuranda and I am very particular about teaching people the threshold braking method It is the first practical thing we do after 2 hours of theory training. This way they are already trained confident brakers by the time I get them to the really steep hills in the afternoon. The 3 most impotant things in any form of driving are the 3 C's Control, Control, Control. I try to keep it simple and practical no fancy left foot braking and complicated intimidating stuff for novices or even more experienced people. On a very steep hills you control your momentum right from the first instance, you can not go too slowly. A slipperry muddy steep hill is one of the worst scenarios in 4wd driving and the only SAFE way to descend is by winching or lowered by another vehicle from a safe position. I agree with what Ken says about making statements or magazine articles without considering people experience or competence. I explain everything in detail to my people before demonstrating and then haveing them do it until they are confident and competent. A picture is worth a thousand words. A demonstration is worth a thousand pictures. Cheers Rob
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Follow Up By: Member - David 0- Friday, Feb 03, 2006 at 16:45

Friday, Feb 03, 2006 at 16:45
I have to agree whole heartedly with the above. As an ex rally man, I have to say threshold braking is the best thing you can teach. Also agree with the muddy slopes comment and let me tell you some of that mud up FNQ is like greased glass- you ought to try it on two wheels!

As far as fancy tricks go, and there shouldn;t be any reason for them in the reptoire of most drivers, but anyway if you really didn't want to use your foot on the brake for whatever reason, I would simply crack a little handbrake on- but again why complicate matters if the foot brake does the job.

The reason I bring up the handbrake idea, is that especially with the patrol 3L Patrol auto ( I own one) if you are stuck on a hill and need to do a reverse descent, a couple of notches of handbrake could save your underpants and probably your car.

Having now advocated that,l I qualify it by saying, please practice it first. It is also a sort of a threshold technique in itself, you need just enough handbrake. Of course the reverse descent is complicated by the fact that the brake bias is towards the front, and when on a slope the front has little or no traction, hence the handbrake which is "biased" 100% to the rear is far more effective in a reverse descent, than the foot brake.

Oops there I go almost as bad as the magazine article. :-)
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Follow Up By: Leroy - Friday, Feb 03, 2006 at 22:12

Friday, Feb 03, 2006 at 22:12
david, with the patrol having a handbrake on the tailshaft I would n't think it would be 'biased' either way unlike a cable to the rear brakes.

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Follow Up By: Member - David 0- Saturday, Feb 04, 2006 at 00:32

Saturday, Feb 04, 2006 at 00:32

Yes it is on the rear tailshaft.

Not quite 100 % biased, true but just as effective.


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Follow Up By: Leroy - Saturday, Feb 04, 2006 at 21:55

Saturday, Feb 04, 2006 at 21:55
David you say just as effective....I disagress. When in 4x4 and having a tailshaft hand brake it's bias to the drivetrain!

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Follow Up By: Rob from Cairns Offroad Training & Tours - Sunday, Feb 05, 2006 at 00:25

Sunday, Feb 05, 2006 at 00:25
I dont reccommend use of the hanbrake and don't use it myself. When we are using the handbrake we are assuming the level of grip will remain contant and this is seldom so. You are right Leroy when you are in 4wd and using a tailshaft handbrake you are, theoretically at least, applying equal braking force to all 4 wheels. As I said I like to keep it simple, low range low and control your momentum from the very first instance. The footbrake is what we are most familiar with and what we have most CONTROL over. If your wheels should lock release and reapply brakes so as to have steering control Assess any situation before you commit, if there is any doubt it can be done safely DON"T DO IT. Cheers Rob
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Follow Up By: Member - David 0- Sunday, Feb 05, 2006 at 08:54

Sunday, Feb 05, 2006 at 08:54
Are the wheels not part of the drivetrain?

The only difference between this handbrake setup and a handbrake acting at the wheel is it is acting ahead of the rear differential. Tell me how that makes any difference if your handbrake in the later scenario is adjusted correctly ie acting equally on both wheels.

Don't disagree with Robs comment about assessing first and agree with keep is simple- however the hand brake technique in the auto Nissan is very affective if you have been silly enough to get yourself in that position.

Regardless of whether you beleive it is actian EQUALLY on all four wheels or not, it is still more effective for two reasons.

1. The footbrake doesn't act EQUALLY on all four wheels it is quite biased to the front. In a steep reverse descent without engine braking this means most of the braking effort is acting on the front wheels- the ones with the least grip. With engine braking no big deal without it- interesting to say the least.

2. In addition to the weight acting on the rear wheels, any force resisting the turning of the rear wheels (and the handbrake does this more effectively regardless of its location) results in a weight shift to the rear further enhancing the grip at the rear. Vica verca, any application of footbrake is much less effective at shifting the weight becasue it doesn't act as effectively on the rear wheels.

The moderation is still done with the footbrake and this is what deals with the varying grip. It works well but like all thsese things, knowledge is one thing, application of the knowledge (skill) is another.

If I was in Rob's position I wouldn't teach it, but it works and works well if you have the skill (though practice) to use it.

Dave O

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Follow Up By: Leroy - Sunday, Feb 05, 2006 at 10:02

Sunday, Feb 05, 2006 at 10:02
I think Rob hit the nail on the head by saying 'When we are using the handbrake we are assuming the level of grip will remain constant and this is seldom so'. If you have your handbrake on regardless of type you can lock up wheels hence not having control. The only real solution is to drive through the brakes to keep all wheels 'driving'.

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Reply By: desert - Friday, Feb 03, 2006 at 11:17

Friday, Feb 03, 2006 at 11:17
That is method of decent that I have taught in the past, when there were only a handful of auto's on the market. These days, there is a plethora of different autos available and the were all a bit different as to how sensitive they were to the reverse/forward technique. I desisted in this teaching method, because it became to complicated to advice each driver on their particular vehicle and transmission. But the theory is sound. You can't do any damage to the gearbox, the greatest danger is stalling the engine which leaves you on a steep slope with no gears,no brakes and no engine control. And that, is the whole point of safe off-road driving in the first place. The only situation where the auto is at a disadvantage is in steep decents and to be frank, in this situation, the potential for a run-away is high. Auto's have to default to brakes and brakes on steep slopes and low-friction surfaces leads to wheel lock-up, which leads to skidding which can lead to loss of control.
AnswerID: 152702

Follow Up By: Member - Duncs - Friday, Feb 03, 2006 at 13:41

Friday, Feb 03, 2006 at 13:41
I drive a manual with no ABS and have used the left foot break drive with the right method on steep slippery decents. I was reasonably pleased with the results but have not done anything that steep for a while.

I also feel that the low range on the GU could be lower, it is certainly higher than the GQ was. For this reason I find I am breaking on steep decents a lot more than I used to in the GQ. Being very careful and willing to lift off the break I have not had any problems doing this, even when towing.

With the Auto does the ABS help reduce the tendency to lock up or does it cut out at low speed therefore allowing the wheels to lock?

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Follow Up By: desert - Friday, Feb 03, 2006 at 13:56

Friday, Feb 03, 2006 at 13:56
I agree with your comments regarding the abysmal low-range gearing in the Patrols. Gearing in Low range is the same for both GQ and GU, however, the many changes to final drive ratio's, now complicate the picture. Also, the GU is much heavier than the GQ. I have fitted Marks Rock Crawler gears to the transfer case, which gives me around 65: 1 reduction in Low first, so I now do not have to use the brakes at all, which is certainly the domain of the manual. However, it is in reverse gear that the real safety benefit comes in to play. I can now key-start in reverse (reduction 53:1) with no hint of run-away due to high gearing like before. Even the manual Patrol was bordering on dangerous in regard to it's rat bleep reverse gear reduction, or lack of!
In answer to the ABS, it cannot react quick enough at the slow speeds that I am talking about. And most cars' ABS is actually not functional in Low-range these days. The ABS tends to cause a worsening of the skid control(as on gravel roads), as it tends to let off the brakes, therefore the car speeds up, you try to brake again, ABS lets off the brakes again and before you know it, you're barelling down the slope at a dangerous speed, and in the auto all you can do is hit the brake! The consequences are not good.
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Follow Up By: Leroy - Friday, Feb 03, 2006 at 15:18

Friday, Feb 03, 2006 at 15:18
desert, you say you can't do any damage to your g'box if decending in reverse. I reckon overheating would result.

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Follow Up By: SteveL - Friday, Feb 03, 2006 at 16:04

Friday, Feb 03, 2006 at 16:04
I also have Rockcrawlers fitted to my GQ,it is far safer than any alternative.The standard ratios are too high and having an auto makes it even worse.-Steve
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Follow Up By: Member - Beatit (QLD) - Friday, Feb 03, 2006 at 16:15

Friday, Feb 03, 2006 at 16:15
G'day Desert,

You've got my attention about the ABS, I can dig the problems it can cause (had the odd lock up that I wanted and that didn't happen because of these) so I figure that presuming one is travelling slow enough in the first place (read low gears), that the ABS would be an advantage by not allowing a lock up when travelling down a steep hill?

Have had one run away in my old GQ, travelling down to Maytown on the Cobb & Co track. The old girl had no ABS and was manual and learnt considerably from the experience. Knew the theory but completely lost that in the heat of the moment - so simple works for me. Hence my question.

Kind regards
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Follow Up By: Member - David 0- Friday, Feb 03, 2006 at 16:46

Friday, Feb 03, 2006 at 16:46
Yes the GU low range is ordinary to say the least!

I believe the home modification lock up torque converotr helps, but I havent tried it YET.

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Follow Up By: Kiwi Kia - Saturday, Feb 04, 2006 at 19:11

Saturday, Feb 04, 2006 at 19:11
Desert, Quote "But the theory is sound. You can't do any damage to the gearbox, the greatest danger is stalling the engine which leaves you on a steep slope with no gears,no brakes and no engine control."

I do hope you don't teach this because you WILL cook a transmission and/or possible kill the person doing it if the ecu deliberately stalls the engine !!! I am afraid that you urgently need to update your technical info about the workings of ecu's and auto transmissions.
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Follow Up By: desert - Sunday, Feb 05, 2006 at 16:20

Sunday, Feb 05, 2006 at 16:20
Kiwi Kia, I did say that I desisted from teaching this technique due to the fact of the matter that the market was becoming flooded with auto's of which the sensitivity to the stall technique was becoming confusing. I fully understand your reticence to understand this teaching, as it is a controversial technique, even amoungst the training fraternity. But there again, I know of instructors that will not advocate lowering tyres pressures either, because it is against what the tyre makers recommend. But we all need to do it from time to time. It's a bit like the novice who it first shown a key start, or a shift from H to Lo on the roll. or the use of a transmission brake, or even using the brakes to help you up-shift on a down slope, all strange and foreign techniques to somebody whom has never been exposed to them before. And you also won't find them in the manufacturers manual either.
Yes, heat is the number one enemy of the auto trans, I learned that in first year mechanics, but just how much heat, that's the subjective part. You are correct though, it is extremely hard to keep abreast of all the different makers technologies with regards to ECU's etc, and I don't profess to know it all, but I do know that most of the driving and off-road techniques are beyond the scope of some makers workshop manual or tech release, they are scratching to understand even the basic terrain apprieciation and off-roading that we do, let alone the innovations of competent mechanics, instructors, engineers etc, whom get out there and ply their craft and are willing to experiment with vehicles, work out what works and doesn't work, and pass on that knowledge to the novice, whom can only stand to benefit from those that drove before them.
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Reply By: Ken - Friday, Feb 03, 2006 at 15:30

Friday, Feb 03, 2006 at 15:30
IMHO this article is another example of the dangerous practice of tossing info around without regard to the skills and experience level of the possible audience.
The technique of driving in an opposite gear to the direction of travel is sound but has some constraints. Extensive use in this way will rapidly heat up the trans fluid as the work being done by the torque converter is greatly increased. You would not want to let anyone know you ever did this in the event of transmission problems!
Most people have little experience with left foot braking in autos or manuals and it is not something to learn on a steep track when things are getting tough.
The technique can take a bit to master, as like a number of things we do 4WDing, such as stall stops, it is quite the opposite action to what we would do on an on road situation. Pushing the accelerator to go slower is not the normal reaction.
Again like left foot braking it is something you need to develop an expertise in.
The technique needs to be fulled explained and practiced regularly to develop confidence and competence. I doubt this would come from reading a magazine article.
There is a risk in prolonged use of this technique and not having seen the article I wonder if this was fully explained. Dave mentions "but not for long periods" not sure if they were his words summariing or the magazine writers. If the later this is hardly good enough.

Driving through the bakes is an new topic introduced into this thread and was not even mentioned in DaveB's opening post. Perhaps from the land of not many hills this is not a well known technique but it is certainly taught in Vic. and as Leroy says it will greatly reduce the risk of wheel lockup on our steep greasy clay surfaces. Skidding wheels neither steer or brake, a couple of things that can be important on stepp tracks.
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Follow Up By: Member - bushfix - Saturday, Feb 04, 2006 at 20:08

Saturday, Feb 04, 2006 at 20:08

yeah I'm a West Aussie living in Sydney but used this technique with success on some very steep and muddy descents on the Deddick trail in the Vic country. Does take some confidence gathering though.
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Follow Up By: Member - bushfix - Saturday, Feb 04, 2006 at 20:13

Saturday, Feb 04, 2006 at 20:13
ah, driving through the brakes that is...
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Reply By: allanmac856 - Friday, Feb 03, 2006 at 16:15

Friday, Feb 03, 2006 at 16:15
Have used the 'reverse gear' technique in my auto pajero & does work very well, but it takes some time to master. I have only used it on very slippery descents where use of brakes, no matter how sensitive you are, is almost useless. One point, & a very important one, is that you are in HIGH RANGE. I'm sure some will find this strange, but it puts far less strain on the vehicle & allows the auto to slip more than if in low range. In regard to distance, 100metres is about the max as the auto can get very hot. The fact of the matter is there are not many really slippery hills,(talking clay here) of this length where I have been in Vic. Even if so, there are sections where you do not need to use this technique.

Great technique to have in the 'bag of tricks', but the reality is you wont use it very often, especially if you can 'drive through the brakes' &/or apply brakes in a progressive manner almost to the threshold point.

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Follow Up By: allanmac856 - Friday, Feb 03, 2006 at 16:23

Friday, Feb 03, 2006 at 16:23
Also, it works even better if stuck half way up a slippery hill & need to reverse back down. Just put in high range then drive, & control your descent speed by use of throttle. The slower you want to go, the more throttle you use. Basically using your throttle as your brake.
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Reply By: Voxson (Adelaide) - Friday, Feb 03, 2006 at 16:50

Friday, Feb 03, 2006 at 16:50
I have used reverse down hills after i have got halfway up and found out because of traction problems i couldnt go any further,,,,and its not much fun in the wet...
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Follow Up By: Voxson (Adelaide) - Friday, Feb 03, 2006 at 16:53

Friday, Feb 03, 2006 at 16:53
oh.. I just read it properly... Reverse gear forwards??? In an auto...
Yeah right hehehhe...
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Reply By: Peter 2 - Friday, Feb 03, 2006 at 17:16

Friday, Feb 03, 2006 at 17:16
When auto's first started appearing in 4wd's they were all manually controlled, basic transmissions, mostly pretty bulletproof. The oppposite gear for the direction of travel generally worked well especially when it was a diesel.
BUT modern electronically controlled trans and vehicles with efi will NOT allow this to occur at any speed over a creep or with any revs on board, the efi will shut the motor down. Then you are left with absolutely no power assistance for brakes and steering and no physical connection to the drivetrain, an accident in progress!!
Driving through the brakes works well but as has been said is hard to learn and doesn't occur naturally without lots of practice.
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Follow Up By: Ken - Friday, Feb 03, 2006 at 23:05

Friday, Feb 03, 2006 at 23:05
Peter, are you sure of this ? You can do it in a GU, Rangie and a Cruiser, are these no modern electronic type vehicles. Are you sure it didn't simply just stall?

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Follow Up By: Peter 2 - Saturday, Feb 04, 2006 at 07:26

Saturday, Feb 04, 2006 at 07:26
We started doing it when auto's first appeared mainly in Jeeps and Scouts in the early days, the reverse gear technique worked well as the vehicles were all pretty basic mechanically and also pretty strong.
Then auto's appeared in cruisers in the mid 80', 60 series and then the turbo middies. It worked really well in the middies and also in the 60's.
Then EFI reared its head followed by auto's with a brain and that's when some vehicles started to 'takeover' from what the driver wanted it to do.
I've personally tried it on Pajero's (2nd gen v6) and the petrol 6 in the 80's and 100's and they all cut the engine when revs rose.
At that point we decided that we would no longer teach the technique to any new 4wders as it was too dangerous.
We were doing it in low range (the hills were way too steep for high range) and the vehicle would only slip for half a vehicle length before the engine was stopped. Then it was a case of keep the bloody thing straight and don't hit anything until the driver could stop it at the bottom without power assistance.
We haven't tried it since except on the Humvee where it worked but was unnecessary due to the very low gearing.
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Reply By: mcgra (VIC) - Friday, Feb 03, 2006 at 22:28

Friday, Feb 03, 2006 at 22:28
this method it taught by the vic 4 wheel association but only on the advanced course, it is stressed for short periods only due to over heating and stress on the torque convertor, i watched it beening done was impressed with the desent.
but agree it should not be just put out there for general use as some who have little to no idea may do the wrong thing.

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Reply By: Rob from Cairns Offroad Training & Tours - Friday, Feb 03, 2006 at 22:33

Friday, Feb 03, 2006 at 22:33
Forget all the tricky stuff, keep it simple, slick mud on clay is treacherous. Our CREB track in the wet is scary and I would never go there in the wet without chains. Just last weekend I was riding with 6 other guys up black mountain road west of Kuranda. Experienced riders on proper enduro bikes. After a brief shower of rain we hit this slick patch of clay and all slid off. It was so sliperry we could hardly stand and we had to help each other pick the bikes up. We hopped back on and were falling off slipping and sliding at 5kph. Thats what the CREB track can be like in the wet but with really steep hills. No driving tecnique will get you up or down safely with out winching or chains. Sometimes you just don't want to be there and what may start as a bit of fun can rapidly end in tears. I hate mud (grinding paste)with a passion. If I dont HAVE to be there I wont. Cheers Rob
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Follow Up By: Member - David 0- Saturday, Feb 04, 2006 at 00:42

Saturday, Feb 04, 2006 at 00:42
Yep been there

11 of us going down the old cairns mail track on mountain bikes- all 11 of us fell in spectacular fashion on a single corner on the hardest red clay you can imagine. It was wet and covered in algae. 11 bikes and riders in one very small pile!

Seen the CREB just as you describe it hence my precautions in the TREK notes on this absolute doddle in the dry and a freakin nightmare when wet!

Jeez I am glad to see someone else passionate about the hatred of mud, Surely the worst off-road driving condition there is. Too bloody hard on vehicles!

I spent an AWFUL amount of time working for the QLD Water Resources Commision now DNR, in QLD black soil country- once you've done it for a living, it isn't fun anymore!

Dave O

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Reply By: Kiwi Kia - Saturday, Feb 04, 2006 at 09:34

Saturday, Feb 04, 2006 at 09:34
I can't believe that there are so many ignorant (technically) people out there who advocate this practice !! Some (most?) modern autos stall the engine when this done !! You are then left with no power assist steering or brakes !!!!!!!

Heaven help anyone who tries this stupid practice. My understanding as to why the ecu stalls the engine is that this practice can cause damage to the transmission and it it is hard to show exactly what led to the failure (cooked). To avoid the problem becoming a warrentee fix (big $) due it being mis-handled by the driver/owner, the ecu stalls the engine. Don't beleive me ? Talk the transmission makers. You may have gotten away with it for a short period in the past but the newer egine management systems don't like it.
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Follow Up By: allanmac856 - Saturday, Feb 04, 2006 at 18:59

Saturday, Feb 04, 2006 at 18:59
Why do you say this. The technique works, & I do not believe I'm ignorant. Fact is, I would rather get the auto a little hot than go sliding into a tree or worse. Also works on late model cruisers/Patrols as I have taught some ppl to give it a go, (in complete safety of course, not on wet/slippery tracks). One had heard of this technique & tried it in low range & had problems. Did it high range & bingo, no worries at all. As I said earlier, must be in high range. Was taught this method by a person who runs a renowned/respected 4wd program in Melbourne.

Each to there own, but there are new techniques out there now that do work. No one, or very few, heard of driving through the brakes in an auto some years ago. Same with auto is hopeless in a 4wd; times change.
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Reply By: jdpatrol - Saturday, Feb 04, 2006 at 10:24

Saturday, Feb 04, 2006 at 10:24
This has been a fascinating post. Good to hear from experienced auto 4wdrivers for a change.

I am a little tired of trainers who have no auto 4wd experience telling auto drivers no brake etc which doesn’t work with auto's on even fairly modest hills. You just have to learn about the techniques being discussed here - for safety sake.

PS I am also a little tired of people saying auto's are not real 4wd's. In my case SWMBO will not have a manual and in town she drives it most. Also, a good 4wd mate cant drive a manual due to a dummy knee which was shot up when he was in Vietnam as a helicopter pilot.

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Follow Up By: Rob from Cairns Offroad Training & Tours - Saturday, Feb 04, 2006 at 15:16

Saturday, Feb 04, 2006 at 15:16
Well I will stick my neck out here as I am known to do and say the only time a manual will work better than an auto is in engine braking as the autos are geared higher and the torque converters allow a degree of slip. This is not so much of a problem these day due to the excellent braking systems modern cars have. An auto and a turbo diesel are a match made in heaven, specially in a big car with a small motor like the Patrol, as the torque converter compensates for tubo lag. Autos run less revs at cruising speeds than a manual due to higher gearing. Its harder to abuse an auto & generally more gentle on the drive train. They kick back seamlessly in sand or dunes. Ideal for towing. Modern autos really are hard to beat and you can drive them like a manual if you REALLY want to with no clutch to abuse. After 30 years of driving manuals and still driving manuals often to the Cape I enjoy my T/D auto and find it pleasantly relaxing to drive. Maybe its an age thing? ;-) Cheers Rob
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Follow Up By: Wayne (NSW) - Saturday, Feb 04, 2006 at 19:19

Saturday, Feb 04, 2006 at 19:19

I would have to agree with you about auto's. There are more and more out there.
When we do driver training the number of auto's out number the manuals.
We have had to concentrate a lot more on how a auto works and how to get the most out of it. It is becoming a real treat to teach someone in a manual these days.
One of the things that we have to do is to get the driver to driver a auto like a manual. Just don't drop it into drive and leave it there all day.

I had the use of a BMW X3 for 5 days, it was a auto, and drive was hardly used. A lot of fun but I don't know if i could drive a auto full time.

If the good lord had wanted us to drive a auto he would have given us only one foot.

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Reply By: Kiwi Kia - Saturday, Feb 04, 2006 at 20:02

Saturday, Feb 04, 2006 at 20:02

Read the text ! Some ecu programmes are designed to STALL the engine if you try this AND you can (will) cook your transmission. Teaching people to use reverse gear for down hill braking could be FATAL. When the engine is stalled by the ecu you will no power assist brakes and no power steering ! Now, how would you like to have a student on a steep slope with the vehicle in that condition - like I said, this could be fatal !

If you are a trainer you should be sticking to the basic, well researched tried and true drive over braking. Also, why do you think auto's have such large brake pedals?

If you don't know the reason that this technique is used then it is back to school for yourself. Hint, it's to do with keeping fluid flywheel engaged and also for traction control including LSD when required.
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Follow Up By: awill4x4 - Saturday, Feb 04, 2006 at 21:04

Saturday, Feb 04, 2006 at 21:04
Unfortunately, Kiwi Kia and others aren't listening to what Allanmac has to say. Now, repeat after me everyone.
" reverse gear braking works in high range not low range" , " reverse gear braking works in high range not low range" , " reverse gear braking works in high range not low range"
If you use low range it will stall, no ifs or buts. If you use high range it doesn't stall.
I've used the technique, been shown how to use it and can say in all certainty that it works.
I don't use it any more simply because of the heat generated into the auto but if I found myself in a dangerous situation I wouldn't hesitate to use it as the downhill control can't be beaten and that includes all you diesel guys.
I use drive through the brakes technique for my auto petrol GQ but am considering changing the low range to a 43% extra reduction available now from Marks adaptors.
Regards Andrew.
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Reply By: Kiwi Kia - Saturday, Feb 04, 2006 at 23:28

Saturday, Feb 04, 2006 at 23:28
To awill4x4

Tell me just one vehicle manufacturer that says that using reverse gear as a brake in an auto transmission is both safe and will not damage the transmission !

If you think it's ok then that should not be hard to do !

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Follow Up By: allanmac856 - Sunday, Feb 05, 2006 at 17:16

Sunday, Feb 05, 2006 at 17:16
Kiwi, not wanting to start a bunfight here, but tell me one manufacturer who;

recommends running tyre pressure higher than on the tyre placard?
taking vehicle anywhere but a dealer for servicing?
Using an auto manually?
Using anything other than manufacturers oil/parts etc?

awill4x4 is correct in saying techniqiue works if used properly, but will be only required on the odd rare occassions, especially if you follow Rob's advice & carefully consider the terrain you drive.

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Reply By: Mike DiD - Saturday, Feb 04, 2006 at 23:35

Saturday, Feb 04, 2006 at 23:35
If I let my Pajero DiD Auto roll backwards while in D High ratio, it will shudder when it gets to about 5km/hr, then stall.

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Follow Up By: allanmac856 - Sunday, Feb 05, 2006 at 00:56

Sunday, Feb 05, 2006 at 00:56
Mike, suprised that happens in your paj, but maybe so. This talk that it doesnt work etc; you see people doing it everyday on the suburban roads !. On a steep hill, stopped at lights for example, in 'D' & using the throttle to keep the car from rolling backwards, bit like how some will ride the clutch in a manual. Dont believe me, have a look out there sometime.
FollowupID: 406921

Follow Up By: Mike DiD - Sunday, Feb 05, 2006 at 08:19

Sunday, Feb 05, 2006 at 08:19
Using accelerator to hold the vehicle stationary when in "D" is a totally different situation to having the vehicle actually moving backwards. The ECU can easily detect the diference and only stall the engine at a set reverse road speed.

On a different theme, the Pajero Tiptronic Auto has a very strong one-way clutch to stop it rolling backwards - only if you shift it to "2" - no need to use ANY Accelerator.

FollowupID: 406936

Follow Up By: allanmac856 - Sunday, Feb 05, 2006 at 11:24

Sunday, Feb 05, 2006 at 11:24
Sorry Mike, didn't mean to put that bit about vehicle on hill in follow up to you. Interesting point about the tiptronic in the newer pajs, but I have no idea as I not driven one in the bush. Mine is a NL with the 4 spd auto & it works well.
FollowupID: 406992

Follow Up By: Kiwi Kia - Sunday, Feb 05, 2006 at 21:05

Sunday, Feb 05, 2006 at 21:05

How many people telling you that this is dangerous does it take before you accept that it should not be taught !

Just because you have gotten away with it does not make it right. I am not argueing to be a smart ass, I am pointing out that this practice will cause a dramatic and possible fatal accident. You don't teach Russian roulette so don't teach this. ALL vehicles - old or new are likely to have their transmission damaged and in some cases the vehicle will run away, end of story and no old wives tale is going to change that. Several people have pointed out that ecu's can detect and stall the vehicle. I am not going to take this any further as its just like talking to a person with their head in the sand.
FollowupID: 407113

Follow Up By: awill4x4 - Sunday, Feb 05, 2006 at 22:42

Sunday, Feb 05, 2006 at 22:42
Mike, I bet you had no throttle input when it stalled and I'd go as far to say I'd put money on the fact if you did the same thing and used the accelerator to balance the car then back off slightly so the car is now going downhill very slowly while your attempting to drive it uphill it won't stall.
Kiwi Kia, both Allenmac and myself have used this technique and know with certainty it works. It's no "old wives tale" if you wish to stick your head in the sand and deny it works so be it. but, you haven't tried it, I have and so has allanmac. This technique originated from America and in extreme 4x4 isn't uncommon over there. Now with ultra low transfer case gears, twin transfers and the like used in competition it is no longer necessary but it's still used by those in extreme country with cars not so severely modified over very short distances.
In the USA whenever people talk about this technique they are always advised to try it somewhere safe 1st and to install an extra trans oil cooler complete with a trans temp gauge.
I'm not advising anyone to use it and neither is allanmac, but when people say it doesn't work without experiencing it especially when forum posters here have used the technique then that's just plain wrong.
Regards Andrew.
FollowupID: 407142

Follow Up By: allanmac856 - Monday, Feb 06, 2006 at 13:36

Monday, Feb 06, 2006 at 13:36
Well said Andrew. If anyone wishes to give it a try, as Andrew & I go to great lengths to point out, do it in safe place & in the DRY. Also, totally agree with your comments to Mike.
FollowupID: 407259

Follow Up By: Mike DiD - Monday, Feb 06, 2006 at 18:10

Monday, Feb 06, 2006 at 18:10
I just tried the Pajero DiD Auto on our VERY steep driveway - if you don't get up all the way in a Manual, you HAVE go all the way down and start again. This would be typical of a track where you really need to be in good control.

I drove halfway up and then reduced the accelerator so it started rolling backwards slowly (leaving it in D, high-ratio). The vehicle started shuddering back and forth - I assume as the ECU tried to reduce engine power to a safe level.

On loose ground, this continuous increase and decrease in power to the wheels (enough to shake the vehicle) would have broken traction - and only made the situation far worse.

FollowupID: 407327

Follow Up By: awill4x4 - Monday, Feb 06, 2006 at 19:46

Monday, Feb 06, 2006 at 19:46
Thanks for your reply Mike. Your's is the 1st vehicle I have heard of which hasn't been able to do this. I used this technique in both my early V6 Pajero and my current GQ without any problems, I have also been in a Jeep Cherokee and L/Cruiser 80 series driven by others in which it has been successfully done as well. That being said, all the times we tried this technique we were going forward down the hill using reverse to slow the car down, so perhaps going in reverse while driving forward is a problem in all vehicles.
If you're prepared to try another experiment on your Paj, try going down your driveway forwards but with the auto in reverse gear, let gravity take your car down but use the accelerator to slow the car but not stop it. I'll be interested to see if your results are different.
Again, please note, I don't use this technique as a matter of course, I only wanted to learn the technique after being shown just how effective it is by a "very" experienced and informed 4x4 trainer who told me it isn't an advised technique due to heat issues into the trans but in certain situations comes in very handy.
Regards Andrew.
FollowupID: 407355

Follow Up By: Mike DiD - Monday, Feb 06, 2006 at 20:15

Monday, Feb 06, 2006 at 20:15
I guess it all depends on how much protection the designer decides to build in to the Auto Box - the Pajero Tiptronic has lots of sensors and it s linked to the engine ECU, so it seems to have lots of protection modes. The DiD throttle is also fully electronically controlled - this is needed for Automatic Stability Control - so teh Auto ECU could tell the Engine ECU to reduce power or shut down the Engine. This would not be possible in earlier engines e.g. Pajero 3.0 or 3.5 V6.

The previous pajero Auto box (1991-1999) also had good protection built in - if you were doing 110k you could change from D to 2 or L - but it was smart enough to realise that it would be fatal so it did nothing.

FollowupID: 407361

Follow Up By: Mike DiD - Monday, Feb 06, 2006 at 22:16

Monday, Feb 06, 2006 at 22:16
Did some more testing on the DiD Auto - I stopped on a hill facing downwards and put it in R. Put on a bit if accelerator to hold it and then let it roll slowly forwards. At less than 5km/hr it shuddered a little and then it stalled.

Went back to testing in D while facing uphill. Put accelerator down so it would hold without brakes, reduced accelerator to reverse very slowly, increased accelerator to hold it again. Took off accelerator to go down faster backwards - engine stalled straight away.

My conclusion for the Pajero DiD Auto - it has been designed to allow holding in D or R, but if it starts moving in the "wrong" direction it will shut down the engine to protect the transmission. This shutdown speed is slower in D than in R. The shuddering which occurs before engine stall will cause wheels to lose traction if you are on a slippery surface.

FollowupID: 407405

Follow Up By: allanmac856 - Monday, Feb 06, 2006 at 23:02

Monday, Feb 06, 2006 at 23:02
Well done Mike on giving it a go, if for no other reason than to satisfy your curiosity. I think you maybe right with all the new 'whiz bang' stuff on the newer pajeros, but the other issue maybe causing the stall/shudder is because it is a diesel ?. Not sure here, but must admit vehicles I've seen do it/showed, have been petrols.

FollowupID: 407421

Follow Up By: awill4x4 - Tuesday, Feb 07, 2006 at 19:26

Tuesday, Feb 07, 2006 at 19:26
A big thanks from me too Mike. Like allanmac, my experiences with this technique have been with petrol's also but it's interesting to note that your vehicle's transmission won't allow you to use this technique.
Thanks for your time and effort in trialling your vehicle.
Regards Andrew.
FollowupID: 407582

Follow Up By: Mike DiD - Tuesday, Feb 07, 2006 at 20:54

Tuesday, Feb 07, 2006 at 20:54
I suspect that 3.8 Petrol Pajeros will do the same thing - since they have electronic throttle control like the DiD Auto.

I assume the earlier designs - 3.0 and 3.5 - which have direct throttle control, will allow reverse travel while in D.

FollowupID: 407606

Reply By: fourstall2000 - Monday, Feb 06, 2006 at 09:17

Monday, Feb 06, 2006 at 09:17
I have a 3.0 litre Auto fitted with Marks rock crawling gears in the transfer case.
It transforms the vehicle,high range unaffected but low range is lower in first than a manual vehicle.
Down hill braking is better than a manual with all the advantages of a auto for hill climbing.
The best of both worlds for $1500 if you fit yourself.
As to the drive through the brakes method, this was invented I believe by landrover for their Autos.
AnswerID: 153281

Reply By: DaveB - Monday, Feb 06, 2006 at 13:26

Monday, Feb 06, 2006 at 13:26
Thanks for all your comments everybody. Gives me some things to try
AnswerID: 153331

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