Thread: Use of handbrake on downhill

Dunno 'bout other makes but never use the hand brake on a Landy.. (Not even to park. Leave the thing in gear instead!)

If first low isn't quite low enough then it's a _very_ gentle feathering of the foot brake. If you're in an auto at the top of a decent, left foot on the brake, blip the throttle to engage the torque converter and then release the brake.

M

Originally Posted by loanrangie

In an auto, light acceleration will lock up the converter then feathering of the brakes gives you better control on steep downhill's.

Originally Posted by camel_landy

...If you're in an auto at the top of a decent, left foot on the brake, blip the throttle to engage the torque converter and then release the brake.

M

I have heard others make similar statements for steep decents with autos, and have always disputed the part about torque convertor lock-up. If someone knows that the methods in the above quotes definitely lock the convertor up I would like to hear it.

I don't have experience with autos in Rovers. But I recall reading that the lock-up of the torque convertor is speed dependant (among, I assume other factors). From memory I think the speed was given as 40 km/hr.

The technique that I pass on to people with autos, is hold a position of the accel pedal, to achieve about 1000 rpm, or a slow pace on level ground. Then use the brakes for the decent.

The reason for the accel position, as explained to me, is to avoid the brakes locking up the wheels. This I can believe more than torque convertor lock-up.

your not revving the engine hard enough to lock up the torque converter just enough to make the converter do some work..

This is going to be crude and simplistic, all those true auto nuts out there can probabley do this better than me (Im not an auto fan) If someone really wants It I'll try a more technical explination of it later

A torque converter is a fancy dancy centrifugal hydraulic pump closely coupled to hydraulic turbine. if engine RPM is too low there is not enough flow/pressure in the converter to allow it to work as designed. Once the RPMS are up it will allow engine braking but IF the rpms drop below a critical speed it all drops off again...

As usual I'm a bit late around to comment on this issue. As it seems there are some around who tried -and succeeded in- using the hand brake effectively downhill without any serious advers effects. Despite this the real facts are not quite in their favour.
On Landrovers, the handbrake works on the rear drive shaft, which implies the rear wheels will lock up if
-you failed to engage CDL (not even an option on Disco II)
-you pull too hardly on the brake lever

Remember that most of the weight of the vehicle on a descent is on the front axle, leaving the rear with less weight on it and much more prone to get locked up. It's up to anyone to imagine the result of locking rear wheels on a steep descent...
If you managed to engage CDL you will have to deal with all four wheels being locked, not the most pleasant scenario either. In case you are a bit careless when applying the handbrake, that is.

I am in favour of cadence braking if things are going wrong, but have to admit I am lacking much experience here as I never was forced to resort to drastic methods when offroading. Careful assessment of the situation is the key. I am using it on icy roads regularly, though, and would never even think about touching the hand brake for that matter as this would almost certainly result in sliding sideways into the ditch.

Originally Posted by Jojo

Despite this the real facts are not quite in their favour.
On Landrovers, the handbrake works on the rear drive shaft, which implies the rear wheels will lock up if
-you failed to engage CDL (not even an option on Disco II)
-you pull too hardly on the brake lever

Remember that most of the weight of the vehicle on a descent is on the front axle, leaving the rear with less weight on it and much more prone to get locked up. It's up to anyone to imagine the result of locking rear wheels on a steep descent...
If you managed to engage CDL you will have to deal with all four wheels being locked, not the most pleasant scenario either. In case you are a bit careless when applying the handbrake, that is.

Real facts?

Use of the handbrake, engaged at the beginning of a descent will apply a constant pressure to the wheels. Use of the footbrake, is subject to constant human interaction and accordingly can easily be over applied through nerves, bumps etc. IMO it is easier to inadvertantly lock the wheels through the footbrake than the handbrake.

The correct technique and that taught by 4wdVic DTU, is to drive through the brakes. In the first instance this is the best method. However, there are instances where additional braking force is desirable. This is more likely in very steep but high traction surfaces.

At the end of the day, it all comes down to not exceeding the traction available. This is something that is different on every descent and can only be learnt through experience. My experience is that in the right situation the handbrake is a useful tool to assist in descending safely.

This has been an interesting conversation. But in all seriousness, what we are talking about is some pretty damn advanced four wheel driving as a rule. It is beyond what most people would do with their family in the car. I understand that using the brakes and possibly the handbrake will work, but to me it's a situation I'd prefer not to be in.

That's why I'm such a big advocate for the rock-crawling gears. I have nothing but praise for them and the difference it made to my Defender was amazing. I know a few people on here have them fitted as well, and I can't say that I've ever heard a bad word said against them other than the initial price.

I might be old fashioned I suppose, but I get real worried when we are depending on brakes or handbrakes do descend a hill. Seems to be taking a rather large risk in my opinion. Best case you get down the hill, worst case you write-off your vehicle and possible seriously harm those in the vehicle.

Just another thought to this thread anyway!

Cheers
Chris

I have the maxi-drive "rock crawling" gears in my auto Rangie. My biggest problem in low 1st on a steep descent is actually stopping the vehicle. At times I have needed to quickly throw it into neutral to get it to pull up.

I think they would be great in a manual with a standard motor but with 35's, a bucketload of torque from the 4.4, and a bloody low final drive, descending steep hills is not something that the gears have actually helped.

For pretty much anything else though they are awesome.

Originally Posted by TuffRR

I have the maxi-drive "rock crawling" gears in my auto Rangie. My biggest problem in low 1st on a steep descent is actually stopping the vehicle. At times I have needed to quickly throw it into neutral to get it to pull up.

I think they would be great in a manual with a standard motor but with 35's, a bucketload of torque from the 4.4, and a bloody low final drive, descending steep hills is not something that the gears have actually helped.

For pretty much anything else though they are awesome.

They are brilliant in a manual. The onlr minor thing that irks me is the straight cut gears get annoyingly loud after a while. Found that out when I was in the Simpson last year!