Driving off road with an automatic gearbox

[sae70]

I had a telephone conversation with Chris yesterday and during this conversation the virtues of having the auto gearbox came up in conversation. After our phone call I sat in the truck to have a closer look at what I have, but my user manual appears to have been mauled by a Doberman and is in three bits with pages missing!!! So, off road, I'm in Low Range, D (drive). Should I turn the overdrive off and what difference could I expect with it off or on. I'm suspecting it only comes into play when in top gear, but I have no idea. Then on the Auto-Box I have P, N, R, D, 2, 1 and then an L. What's the L all about?!

 

[SpinDrift]

I would have thought that OD only kicks above a certain speed - over 40/50mph, and that you would be unlikely to reach that speed in Low Range.

 

[Chris]

Stick it in drive, high range and see how far you get. Then if you need a bit more push the lever forward and lock the centre - Stephen this is no different to what you had before you know. Then into low and you can then lock the rear too.


When in D, the box will cycle from 1st up to top. When in 2 it will start in 1 and change up to two. When in 1 it will only ever be in 1st. Come on man, you can't seriously be asking this. If you have a button called second start, this locks out 1st gear when in 2 at the shifter. So it's locked in second gear. Quite handy when in low range. It stops the box kicking hard into second so that you lose traction. So your options are now, 1st only, 1st and 2nd, 2 only, 1st, 2nd and top or 2nd and top. See?

Chris

BTW, when going down really steep hills, to get better control, knock it into neutral. Not for engine braking situations of course. Biut the torque is so huge in low 2st that it will push you against the brakes. It's like dipping the clutch effectively

 

[Gary820]

What's the engine braking like going down steep stuff? Still getting used to an auto off road and like it going up and over obstacles. Not pushed it hard yet or done not any big descents.

 

[Chris]

Forwards it's alright. Not as good as a manual. There is a lag between plummeting and the engine catching you up. You just have to be brave.

In reverse? Utterly terrifying.

 

[Gary820]

Will get plenty practice, Tbh going from a manual diesel with auto front locker and ifs to the 80 has been a learning curve!

 

[goodoldboy]

What's the engine braking like going down steep stuff? Still getting used to an auto off road and like it going up and over obstacles. Not pushed it hard yet or done not any big descents.

the "dont brake whilst going down hill" thing seems to be a bit misunderstood by a lot of 4x4 drivers - if its slippy no braking/engine braking is fine but if there is grip braking is ok - i have a "flight of steps " on the entrance to my property& always go down on the brakes

 

[tim falce]

What's the engine braking like going down steep stuff? Still getting used to an auto off road and like it going up and over obstacles. Not pushed it hard yet or done not any big descents.

I use it in snow when the car will just slide uncontrollably using the foot brake. I put it in low ratio and shift the selector to 1 and have never had a problem on the really steep hill by our stables gate.

 

[fast but dim]

the "dont brake whilst going down hill" thing seems to be a bit misunderstood by a lot of 4x4 drivers

IMO that's the only change you need to make when driving an auto offroad. I've always preferred autos offroad. Shame I have a manual.

 

[thewormman]

The other good thing about an Auto is what's called the poor mans diflocker. Basically if you have a wheel in the air and its spinning you are effectively down to one wheel drive. This is in normal drive nothing locked. If you just gently put your left foot on the brake while feeding in the power the drive will be transferred to the wheel on the ground.

An unlocked diff will transfer the power to the wheel with least resistance, so by gently braking the spinning wheel will lock and voila the wheel on the ground will get the traction.

Useful if on a track or something where you don't want to start shifting levers for the sake of a couple of potholes where you got cross axled.

 

[clivehorridge]

I don't know the auto box at all as I've only ever driven a manual 80 (had an auto Pajero for 18 months but that doesn't count) and decents sound similar to the way I drive my manual offroad. I've got a few steep and slipperies on my favourite runs and I'd much prefer to engine brake down them in the low box than brake. Braking in higher gears generally means you have almost zero control of the car, if it's slippery enough.

I remember once in a Terrano, very icy and I drove up a steep narrow hill with a 90 left at the bottom and a 90 right at the top. I was almost to the top, praying nothing would happen to make me lose momentum, and a clown in a X5 came down from the top and forced me to stop. Immediately I stopped, the car started to slide backwards on the ice. I went from top to bottom, even managed to negotiate the bend, but I didn't stop until a kind chap in brand new Dacia pick-up got in my way... then I stopped!


It's scary when you're out of control, especially if you're on your own on the mountain.

 

[Gary820]

Not in for the poor mans diff lock, much rather turn the switch