Thread: prolonged use of hill descent control

Originally Posted by Pedro_The_Swift

disregarding the HDC for a sec,,
The D2 has an issue with lack of revs and the Torque Converter,,
no revs = no lockup = runaway car!
all can be averted by actually driving the car downhill,

Just started a thread in the D2 forum regarding this puddle of "Bad Oil"....

http://www.aulro.com/afvb/discovery-...p-braking.html

My experience off road (without a trailer ) mirrors garrycol's. I use an appropriate gear 1st or second low range and have never had a runaway. In the event that the incorrect gear is selected pressing the yellow button quickly brings the vehicle safely to a condition where you can easily change to a lower ratio.
I would imagine that the torque converter is locked by the computer on downhill runs anyway so a runaway is not possible due to a lack of engine braking.

Regards,
Tote

Originally Posted by paddy119

Hi, Just a quick question regarding the prolonged used of HDC, i will be towing a off-road camper trailer that will be fully loaded up (it does not have brakes), we will be going to a camp site called west Kunderang in the wild oxley rivers NP, near Armidale, i am told that to get down to the valley there is a fairly steep long sections of downhill to negotiate,

My question is do i continue to use HDC and low range auto, or should i disengage HDC and engage 1st gear low range and use the brakes in short sharp bursts to stop over heating?

I there a chance of HDC over heating brakes?

Thanks Pat

Pat,

Whilst not with a camper trailer I used HDC to descend from Mt Pinnibar in the Vic High Country once due to a transmission fault that mean I had a concern with relying on 1st low range.

The decent was very steep and very long and I had no problem with over heating but did stop on the flatter sections for short periods as a precaution. In saying that I did not once get that burning brake smell or any sense of the vehicle not handling the prolonged decent with HDC.

I would guess (and it is a guess) that as long as you take it easy, are aware and cautious the HDC combined with 1st low would handle most steep descents.

I have not idea about trailer brakes so will leave that to other to discuss.

Enjoy the trip, I hope you can put a report up in the trip reports section once complete.

George.

no, not comparing, maybe just a bit of a hint is all,, but if what garry says about the resetting of the speed everytime,, it doesnt look like LR fixed the problem.

As all have said,, put brakes on it next time

Thanks for all the advice, i have used HDC for short downhills and have been impressed with its control, i think i will use a combined approach of low gearing and HDC and inspect brakes periodically, i will let you guys know how the trip goes, only 2 weeks to go, West Kunderang, Byron Bay, Noosa, then off to Fraser Island for a week. Cheers

dont worry so much about the brakes themselves...

worry more about the ABS module.

IF youve been working the TC HDC and ABS hard it has the potential to overheat and shut down. It doesnt mean the brakes are gone but it does mean you have to drive old school without the electronics untill the pump cools down and restarts.

Does anyone know if HDC applies the brakes evenly across all 4 wheels?
From previous experience when I used HDC for a long descent in a D2 after the transmission went into limp home mode was that it doesnt.
When I reached the bottom smoke was pouring off the right rear wheel, whilst the others seemed ok. In hindsight I would have been better off manually applying the brakes.

Originally Posted by amaruskanic

Does anyone know if HDC applies the brakes evenly across all 4 wheels?
From previous experience when I used HDC for a long descent in a D2 after the transmission went into limp home mode was that it doesnt.
When I reached the bottom smoke was pouring off the right rear wheel, whilst the others seemed ok. In hindsight I would have been better off manually applying the brakes.

At a rough guess, i would expect that it would not apply the brakes to any wheel that had no traction, such as one that was not touching the ground.