Wonderful downhill shifting behavior with 8 speed auto

sigsegv

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I finally got my Jeep today!

I have a steep paved driveway and have to traverse some pretty steep hills to get around my neighborhood.

I've read a lot of threads here but none have mentioned how the transmission seems to be programmed to behave on downhill stretches with your foot off the gas. It is really resistant to upshifting and does a great job of not letting the car accelerate as if rolling with no engine resistance. If you press the gas pedal a bit it starts acting more like I'm used to with automatics, and lets gravity do its thing.

Am I crazy in thinking the JL behaves differently than most autos in this respect? I really like it - it's like a minor version of hill descent control but without applying the brakes. Most autos I've driven will engine brake, but they are programmed to always be in as high a gear as possible for a given speed when you take your foot off the gas and coast. The JL seems to not do that when it's pointed downhill.
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WXman

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I mentioned it. I HATE it. It feels like using tow/haul mode on a pickup truck, except you're not towing or hauling. I don't like it at all. I have to keep a foot gently in the pedal just to drive down country roads in order to maintain speed down a hill, which of course prevents the fuel injectors from shutting down and burns more fuel. I think Jeep got really carried away with the engine braking in this transmission program.

Thankfully, there'll apparently be programmers out soon and maybe we can clean up this transmission shifting through the aftermarket.
 

Sean L

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I haven't seen this at all in my Jeep, If I want to engine brake I have to go into manual mode and downshift several times before I feel any appreciable engine braking for downhill driving.
 

MacBigButt

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I agree with the OP, I live in a hilly/mountain terrain. The 8-Speed sits in a gear very well, more or less lined up to the speed you are travelling. If you want a lower gear, brake a bit and it downshifts and holds the new gear. If you want a higher gear, speed up enough to upshift and it holds that gear. Kinda of an automatic-manual effect. I don't remember any of my other vehicles doing this as effectively.
 

FulThrotl

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I finally got my Jeep today!

I have a steep paved driveway and have to traverse some pretty steep hills to get around my neighborhood.

I've read a lot of threads here but none have mentioned how the transmission seems to be programmed to behave on downhill stretches with your foot off the gas. It is really resistant to upshifting and does a great job of not letting the car accelerate as if rolling with no engine resistance. If you press the gas pedal a bit it starts acting more like I'm used to with automatics, and lets gravity do its thing.

Am I crazy in thinking the JL behaves differently than most autos in this respect? I really like it - it's like a minor version of hill descent control but without applying the brakes. Most autos I've driven will engine brake, but they are programmed to always be in as high a gear as possible for a given speed when you take your foot off the gas and coast. The JL seems to not do that when it's pointed downhill.
yup. it does that. first noticed it some trails where there were steep downhills for a little bit.
does it in 4wH. at first i thought it was hill descent, but that was not turned on. it'll just plonk
down the hill till you nudge the gas.
 

Sgt Beavis

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I definitely noticed it when driving through Rocky Mountain National Park yesterday. It works quite well IMO.
 

k9jackie

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Ok, glad I’m not the only one who noticed this...I don’t not like it at all. I live in a very hilly area with winding roads and hills. I’m having a hard time getting used to how it shifts and it almost makes me nauseous because it doesn’t accelerate/decelerate on hills like most other vehicles
 

Jallenb11

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My Challenger was the same. When cruise was set you could feel it downshift to maintain speed going downhill. Felt the same thing with my Jeep going through the mountains in West Virginia.
 

Jrbrannan

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Ok, glad I’m not the only one who noticed this...I don’t not like it at all. I live in a very hilly area with winding roads and hills. I’m having a hard time getting used to how it shifts and it almost makes me nauseous because it doesn’t accelerate/decelerate on hills like most other vehicles
Throw it in manual shift mode. It isn't perfect but much better than normal.
 

Tridgerat

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I love it. I use cruise control a lot and it maintains speed damn near perfectly through all the hills around here. My old car would drastically speed up going down hill when the cruise was on before the transmission would shift and slow it down. My JL hardly gains a single MPH. It's definitely nice when hitting the trails too.
 

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i dont like it when you brake going down a long hill and then a turn at the end of the hill. feels like the brakes are locking up.
 

Col Oliver

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I like it. I travel lots, lots of back roads. I like this trans a lot, from my challenger to the jeep... smooth shifts, quick shifts..
 

tcadaniel

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I love this feature. My brakes should last forever!!!
 

subiescott77

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I definitely noticed it when driving through Rocky Mountain National Park yesterday. It works quite well IMO.
It does, I like it as well.

OP...it for sure is engine braking. Keeps the wear off your brakes and also helps fuel economy. I'm not exactly sure how or what type of a brake it is....but it's decent.
 
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