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Driving on steep downhill highway grades

Jeep Junkie

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Guys, how to stop the Jeep from accelerating? If I manually downshift, the engine screams. How to keep the Jeep between 45 and 55 mph without braking? On the trail 4Lo/2nd gear does great.
Thank you!
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Guys, how to stop the Jeep from accelerating? If I manually downshift, the engine screams. How to keep the Jeep between 45 and 55 mph without braking? On the trail 4Lo/2nd gear does great.
Thank you!
Gears- down shift , use together with the brakes to not over rev, and they will also stay cooler by using compression braking. Quite simple.
If not for compression braking via a Jake Brake I likely wouldn’t be here to write this after a brake system fail releasing them with slight pressure just over the top of the old Pacheco Pass with 80K lbs pushing. Wheels off the ground in curves, it took miles to get it stopped after surviving to the bottom. Way over revved, F’ the Cummins This Guinea pig with a new trailer with the new anti skid brakes. They were kept out of service until resolved.
 
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Jeep Junkie

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Gears- down shift , use together with the brakes to not over rev, and they will also stay cooler by using compression braking. Quite simple.
If not for compression braking via a Jake Brake I likely wouldn’t be here to write this after a brake system fail releasing them with slight pressure just over the top of the old Pacheco Pass with 80K lbs pushing. Wheels off the ground in curves, it took miles to get it stopped after surviving to the bottom. This Guinea pig with a new trailer with the new anti skid brakes. They were kept out of service until resolved.
So I downshift manually to, say 4th gear, and then brake if it over revs?
 

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So I downshift manually to, say 4th gear, and then brake if it over revs?
Essentially, I could look up the V6’s power band and redline but you should already know them. Don’t wait until redline, just apply enough brake as needed to maintain the chosen speed in the proper gear.
 

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Essentially, I could look up the V6’s power band and redline but you should already know them. Don’t wait until redline, just apply enough brake as needed to maintain the chosen speed in the proper gear.
Roger! My stupid redline is like over 5000.
And thanks for showing off your 392 to the 3.6 peasants 😃👍
 
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Wow, my redline is 6000. So anything below is safe?

Jeep Wrangler JL Driving on steep downhill highway grades Screenshot_20250612_210023_Gallery
 

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I havent tested this on the Jeep as I normally move to manual and use lower gears and tap breaks slightly to control speed when going downhill. I also have regenerative braking that helps a lot.

I was driving via some steep grades early this week in my Ram, running it on ACC, Ram would automatically downshift to maintain the chosen speed. Should work the same way in Jeep
 

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I havent tested this on the Jeep as I normally move to manual and use lower gears and tap breaks slightly to control speed when going downhill. I also have regenerative braking that helps a lot.

I was driving via some steep grades early this week in my Ram, running it on ACC, Ram would automatically downshift to maintain the chosen speed. Should work the same way in Jeep
I had the same vehicle combo before swapping my Ram for a 2500HD. The Ram with the 8 speed did an awesome job downshifting to maintain. I'm pretty sure when I overcome regen the Jeep wasn't as good in the downshift department.
 

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I had the same vehicle combo before swapping my Ram for a 2500HD. The Ram with the 8 speed did an awesome job downshifting to maintain. I'm pretty sure when I overcome regen the Jeep wasn't as good in the downshift department.
Very much possible. I have noticed the ACC implementation on Ram (mine is '19, 1500 L) is far better than the Jeep
 

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Very much possible. I have noticed the ACC implementation on Ram (mine is '19, 1500 L) is far better than the Jeep
Didn't have ACC on my 19, but the Ram would do whatever it needed to to hold within a mph even towing using standard cruise on steep declines.
 

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I havent tested this on the Jeep as I normally move to manual and use lower gears and tap breaks slightly to control speed when going downhill. I also have regenerative braking that helps a lot.

I was driving via some steep grades early this week in my Ram, running it on ACC, Ram would automatically downshift to maintain the chosen speed. Should work the same way in Jeep
I've trashed brakes in vehicles with that approach. $4,800 to replace the front rotors in my last RS-5 after descending into New Mexico from Colorado.

From my testing it looks like my JLURD does the same thing: brakes only w/o downshifting.
 

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From my testing it looks like my JLURD does the same thing: brakes only w/o downshifting.
That would be horrible for long and steep downgrades
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