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Any Fix for the Awful Rev Hang?

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TwelveGaugeSage

TwelveGaugeSage

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I had a manual TJ and a manual JK as well. It wasn't a thing on the TJ and the JK manual never sat well with me. It just felt clunky. I could never get past that or the crummy location of reverse long enough to notice rev hang or lackthereof. It went to my ex in the divorce, lol. The JT transmission is wonderful. The rev hang plus manual is annoying to me, but still way better than being stuck with an automatic.
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I had a manual TJ and a manual JK as well. It wasn't a thing on the TJ and the JK manual never sat well with me. It just felt clunky. I could never get past that or the crummy location of reverse long enough to notice rev hang or lackthereof. It went to my ex in the divorce, lol. The JT transmission is wonderful. The rev hang plus manual is annoying to me, but still way better than being stuck with an automatic.
A TJ is still controlled with a real throttle cable, so no rev hang there. This started after everyone went drive by wire, and it's for emissions purposes, the same reason they went drive by wire. And yes, the reverse position on the JK is stupid. It's really the only thing I don't like about ours. It makes it awkward, and hard to shift into reverse. Still haven't gotten used to it. But that one's my wife's, and I guess she has.
 

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Two things I have adjusted in my driving style for this transmission (my 5th MT vehicle) is shifting a little higher during normal driving and a soft release of the throttle before depressing the clutch. This has seemed to reduce the effect of the rev hang and smooth out shifts. I typically hit 3k for my 1-2 shift.
 

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Two things I have adjusted in my driving style for this transmission (my 5th MT vehicle) is shifting a little higher during normal driving and a soft release of the throttle before depressing the clutch. This has seemed to reduce the effect of the rev hang and smooth out shifts.
I can appreciate that point, I had to make a similar adjustment. I noticed compared to prior (4) manuals, my JT clutch engages very early when you let off (near the bottom). So I have to make an extra effort to make sure the clutch is fully in before beginning to let off the gas during an upshift, or I can get a jerky transition. My only gripe I would say, makes shifting a little less natural for me.

I'm hoping there's a way to change the engagement point just a bit, if I do the Centerforce unit later. Would make it easier to switch between the JT and Camaro mechanical clutch which is the exact opposite engagement haha.

Sorry not really rev hang related, I actually think that's better on my JT compared to my previous trucks. Carry on.
 
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A TJ is still controlled with a real throttle cable, so no rev hang there.
That doesn't really make the difference. The engine I put in my SX4 is out of a 94 ZJ. Of course it's got cables (one for throttle pedal the other for cruise)
I noticed right off the bat after putting it all together and taking it for the first drive years ago that when pushed the clutch in and shifted to neutral and came to a stop sign the RPM stayed up at about 1200-1400 and slowed to 750 as I slowed. It didn't drop to idle until I came to a stop.
Clutch in or clutch out and in neutral, either way, if my foot is off the gas pedal it won't drop to idle until the car stops. I can hear it or watch the tach and that needle doesn't drop back down to under 800 until the car stops rolling. It's even worse when it's cold outside.
So they were doing that even in the 1990s.

My bet is that it's emissions related.
 

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The Livernois tune fixes this as much as possible.

* They aren't replacing your flywheel.
 

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I've driven many manuals and never noticed rev hang - except when the motor restarts after Auto SS (is that Stop Start, or Start Stop? :D) and I shift from first to second gear. Going into second, I've learned there's no need to give any throttle. Seems like fuel delivery is a little over eager or something. Everything's back to normal by the time I shift from 2 to 3.

Usually solve all of this by remembering to disable Auto SS.
 

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Just like others have said, 2000 miles in and I'm pretty much used to it. It did freak me out at first, but I barely notice it now. I think I subconsciously adapted to it with a slightly different method of driving. ?
 

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Thanks! ?You have to find a Nacho and a manual, though. Two rare options, so I'm guessing even rarer together ;). In my case, I just bought from dealer stock haha. It was easy finding new vehicles back then (way back in April 2021 haha). And the local dealer stocks a lot of 6 speed Wranglers and Gladiators, though they never stick around long.
Update. Buying the last new Nacho, and it's a manual. Flying to get it Sunday. Freedom edition.

Can't wait to drive this manual and see how it differs from my JK. Also hated the reverse in the jk, bad placement when you have a drink in the front cup holder
 

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Update. Buying the last new Nacho, and it's a manual. Flying to get it Sunday. Freedom edition.

Can't wait to drive this manual and see how it differs from my JK. Also hated the reverse in the jk, bad placement when you have a drink in the front cup holder
Congrats! Compared to your '13 JK I think the most noticeable differences will be in the JT:

- lighter clutch pedal
- taller reverse gear
- short range in first gear; long in second

All should be easy enough to adapt to. Just feels a little odd at first.
 

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Update. Buying the last new Nacho, and it's a manual. Flying to get it Sunday. Freedom edition.

Can't wait to drive this manual and see how it differs from my JK. Also hated the reverse in the jk, bad placement when you have a drink in the front cup holder
Awesome! I found the JT transmission and clutch feel to be far superior. Whatever you do, don't judge it too harshly until you get some better gears and a throttle controller. The 3.73 gears were definitely a mistake on Jeeps part. They should have just put 4.10s in everything. People complain about the Pentastar being a bit of a dog, but I don't feel that way at all.
 

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My 21 JTR auto had rev hang when heavy on the accelerator from a stop then let right off, rev would stay up there. First time my wife experienced it as a passenger she looked at me and said “what’s wrong with it, is it broken?!” I said “NO, it’s learning driving habits and adapting”. I asked my Service Manager about it and he commented that off the start with a heavy throttle then you let off, the computer still thinks you are in a “sport” mode of driving and keeps it in that rpm and gear until it senses you’re not and settles down.

I had just lived with it UNTIL I did a full hot flush of the transmission oil (found out @ 24k kms I had glycol and high copper and iron count in the tranny) and replaced it with a ZF compliant full synthetic and tranny shop reflashed the tranny, the rev hang stopped. It’s been 8k kms later and still have no rev hang.

Tranny shop said it takes 10k kms for the “learning process” to finalize.
 
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Tranny shop said it takes 10k kms for the “learning process” to finalize.
I think with the manual transmission, the only learning process is the one the driver goes through.
 

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I agree with the revving higher and lifting gas before depressing clutch. The rev hang on the 2.5L colorado MT I had was WAY worse. It felt like 5 seconds before the revs started to drop. Awful vehicle, GM is the worst.

I have 3.73 and don't feel like it negatively effects anything. I just put the pedal to the floor and hold the revs higher. I'm running 32s though and will never go larger. I'd humor gears to make reverse better for backing trailers though. I don't know why they think we need to go 45 mph in reverse.
 

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I can appreciate that point, I had to make a similar adjustment. I noticed compared to prior (4) manuals, my JT clutch engages very early when you let off (near the bottom). So I have to make an extra effort to make sure the clutch is fully in before beginning to let off the gas during an upshift, or I can get a jerky transition. My only gripe I would say, makes shifting a little less natural for me.

I'm hoping there's a way to change the engagement point just a bit, if I do the Centerforce unit later. Would make it easier to switch between the JT and Camaro mechanical clutch which is the exact opposite engagement haha.

Sorry not really rev hang related, I actually think that's better on my JT compared to my previous trucks. Carry on.
you'll love the Centerforce clutch - its awesome!
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