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I can use hill descent but sometimes it's just too slow. I try using first or second gear in regular or 4WD Low mode. The car holds back, but often the car will start picking up speed as the revs head toward the red line. Brakes work fine but I don't want to overheat them, so what advice do you 4 wheelers have for me to control downhill speed when not using hill descent. Thanks in advance.
 

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I think that's unfortunately how it drives.

Not sure if that's a function of protecting the PTU or if it's just how the engineers choose to make it.

But it sure would have been REALLY nice if it would automatically engage engine braking above a preset rev limit, like my old WJ did.

Or even better, to have a simple pushbutton on the steering wheel to engage "max engine braking" when pushed and held.

Hill decent is just a gimmick. Sure, it works. Really nice, actually. But only in 4 low. And I sure don't have time on the trail to keep fiddling with the settings every two hundred meters.

It's bad enough I regularly have to go into 4-Low just to make sure I have torque when I need it. Plenty of torque out of the V6, but the software repeatedly refuses the engine to rev on steep inclines in 4-Hi which makes going up as frustrating as going down.

On the plus side, I've never had issues with the brakes not being there whenever I needed them. So I'll just keep manually selecting the low gears and using the brakes to keep the revs under 4000.
 

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What I have determined in my 2014 V6 TH driving in 4 low is that slow is better, just fast enough to have enough momentum.
I drive up and down my 30 degree rough and rocky fire trail in second gear, sometimes first and sometimes third.
Have never had the TH run away in 4 low. It will in 4 high so I downshift before I start going downhill.
The transmission seems to free wheel until it engages a gear.
I have led Wranglers on my drives and I can tell I am really slowing them down.
They drive over obstacles with ease but I have to slow down a lot so I don't tear off the rear lower control arms.
 

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Discussion Starter #4
...Have never had the TH run away in 4 low. It will in 4 high so I downshift before I start going downhill...
Are you saying you think my car has a problem, or that's just the nature of the beast?
 

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If you are in 4 low using hill descent mode in first or second gear and the Jeep speeds up or the engine revs a lot higher there is a problem.
The brakes should keep you at the selected speed no matter what.
The brakes control your speed, engine braking not so much.
 

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Discussion Starter #6
If you are in 4 low using hill descent mode in first or second gear and the Jeep speeds up or the engine revs a lot higher there is a problem.
The brakes should keep you at the selected speed no matter what.
The brakes control your speed, engine braking not so much.
No problem in hill descent. Just a little too slow for some conditions so I try NO hill descent and just shifting back and forth between 1st and 2nd. The car will hold and hold then it just takes off as the tach heads for the red line. Brakes work fine. Just afraid of overheating them.

Imagine this: I'm coming down a county road on a ski slope with long descents and switchbacks. In Hill Descent other cars are trying to pass me; going faster isn't dangerous as long as I can keep the speed under control. I'll ride the brakes all the way down if it's okay to do that. What do you think?
 

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How fast are you trying to go? Hill descent control maxes out around 5 mph. The scenario you describe above sounds like road driving, where HDC is meant for off road use.

I guess you’re expecting more engine braking, but there isn’t a huge amount. Manually controlling the gears and using the brakes is probably your best bet.
 

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Discussion Starter #8
How fast are you trying to go? Hill descent control maxes out around 5 mph. The scenario you describe above sounds like road driving, where HDC is meant for off road use.

I guess you’re expecting more engine braking, but there isn’t a huge amount. Manually controlling the gears and using the brakes is probably your best bet.
I hear ya. I guess I'm wondering why the car holds and holds and holds in lower gears and then just lets go. Watching the tach it's obvious I'm still in that lower gear when it happens, but I've never had this problem with other auto transmissions.
 

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The 9spd is a mysterious thing!

Maybe the RPMs go up because the descent got steeper? When I’ve come down some steep roads in the Sierras, putting it in manual and limiting it to 2nd or 3rd has done a decent job of limiting downhill speed. I may still need the brakes, but not as much as if I left it in full auto mode.
 

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The 9spd is a mysterious thing!
Is that true or what :) .

Mine holds sometimes. It's unclear what triggers the hold/engine braking but it does it sometimes. Touching the brakes or accelerator, or if the revs build due to slowly running up the speed, causes all engine braking to cease and I'll have to compensate with the brakes. Slowing down and re-selecting a suitable gear sometime restores the engine braking. Sometimes not. So far I haven't found a pattern.
 

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No problem in hill descent. Just a little too slow for some conditions so I try NO hill descent and just shifting back and forth between 1st and 2nd. The car will hold and hold then it just takes off as the tach heads for the red line. Brakes work fine. Just afraid of overheating them.

Imagine this: I'm coming down a county road on a ski slope with long descents and switchbacks. In Hill Descent other cars are trying to pass me; going faster isn't dangerous as long as I can keep the speed under control. I'll ride the brakes all the way down if it's okay to do that. What do you think?
Is there some reason that you don't want to use the breaks? I have a 2019 TH and I have yet to overheat the breaks, nor did I ever overheat the breaks in my 08 Dodge Caliber (that thing has a CVT with AWD and 2.4 engine braking was not it's particular happy spot unless you wanted to be bouncing off the rev limiter in manual mode) and I have used just the brakes coming down the mountain passes here, heck coming down the mountain thats like a hour from my house (it is steep ski slop type slops (mater of fact at the top of the mountain are ski slops) with sharp switchbacks (the speed limit down the steep part of the mountain is 35 because of the turns and it has quite a few that drop down to 20-10 MPH. I don't think I have driven a modern car where I have overheated the brakes on any road driving that I have done. So I would say just use the breaks as that seems like the easiset solution to your problem and you will be fine.

And yeah Hill Decent control is really targeted at off roading when you are trying to slowly make your way down a step incline. I have used it once (ironically on my 2018 limited that I owned during an off road camping trip where I then decided I really really really wanted a TH so I treaded it in on my 2019 TH) I used it on a very steep incline that had lost of rocks and ruts and was basically single lane switch backs which then allowed me crawl down focusing on picking the best lines to deal with the rocks and such.
 

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I use adaptive cruise control when driving through the mountains, whatever speed you set it to, it will slow itself down to that speed. If its really hilly mountainous area where you also have to drive up, put it into sport mode so the shifting isn't so severe.
 
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