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Summarize the 6MT Situation For Me

LKG

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Sounds like there's a great "Crime Watch" story in there somewhere.... but, like you, I would certainly buy another MT. I just can't figure out why Jeep refuses to let me option out my dream Jeep; 2-dr, 392 Hemi, MT with 4.88s:
Dream Jeep.webp

Credit: I "lifted" this from some other forum member who initially posted it. In a nutshell it IS my dream Jeep.
Right... Nobody died and I got a great upgrade so it had a happy ending, for me at least.
I think a 2 door with a 392 would be terrifying, but a good terrifying🤣
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LSJKU

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Okay, but you aren't going to have this weak ass manual transmission behind V8 Power and expect it to survive. Give me an NVG4500 and let me row tractor gears, I'll be happy as hell.
Yes, you're correct, sir! Would really love that granny gear in the NV4500, but I decided on the Tremec T-56 (TR-6060) a long time ago. It's an all around better manual for everything BUT rock crawling. Plus, the NV4500 takes more mod's to make it work.

But... if somebody wants to donate an NV4500 to the cause, I wouldn't turn it down. How awesome would that be, rowing truck gears and crawling around in a 5:1 or 6:1 granny gear with the 4:1 Rock-Trac? Then again, I'm assuming the Rock-trac will work with either. I would need adapters, a different shaft or, most likely, a different transfer case altogether. I haven't dug that deep into it, just recalling the LS/16L80 swap in my JKU. I had to go with an aftermarket NP transfer case for that swap.

And then there are the axle considerations with all that torque on tap with no converter to manage it... oh man, it get's really deep very fast. That's why Stellantis should give us the opportunity to order what we want; get it right from the factory to begin with.
 
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LSJKU

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In reality, it may be too much to think I can actually pull off a 392/Tremec swap. I would likely just go with the 8HP70 because I could source it all as one item from the junk yard and not worry about building an SRT/Tremec Frankenjeep. But i sure would miss the manual. That's one reason I did not go with the 392 from the factory. That and I wanted a 2-door Jeep, not a 4-door. Se la vie!
 

bllprk

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How long have you had your CF clutch and how do you compare it to the factory one?
I have had 3. I love it when it works.

1. Purchased my 2018 JLU with 44,000 miles. Threw on 33's right away. Tried to teach my 15 year old a MT and he just couldn't make it work. The clutch was on or off.

2. Re-gear to 5.13's with 35's. He still really struggled to figure it out. 64k Miles

3. CF's second try at a JL Clutch - CFII - External Slave - 65k miles. It worked amazing. Totally different than stock. Feathering great. Moab Trip. My son figured it out instantly. Didn't pay much attention to cleaning the input shaft spline / probably added too much grease.

4. With 10k Miles on it, clutch started acting up. Hard to get it into 1st and reverse. Accidentally filled the bell housing with mud and destroyed the rest of the clutch.

5. Cleaned out the clutch, and while waiting for a new clutch, put the old one back together. Clutch worked again and shifted great. (cleaned input spline)

6. A week later installed a new CF clutch (same one) but with Internal Slave. Very small amount of grease on input shaft. LOVE the feeling of the internal. Easy press. Easy bleed. Used this setup for 30k miles. Started to not like 1st. Started to get stuck in gear when I started the engine.

7. At 105,000 replaced the clutch. This time CF said no lube on the spline. Its pre-lubed with a dry lube. Super cleaned the spline. Love the performance again. Sitting at 5000 miles on new clutch. Hoping for the best
 

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jeepingib

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Yes, you're correct, sir! Would really love that granny gear in the NV4500, but I decided on the Tremec T-56 (TR-6060) a long time ago. It's an all around better manual for everything BUT rock crawling. Plus, the NV4500 takes more mod's to make it work.

But... if somebody wants to donate an NV4500 to the cause, I wouldn't turn it down. How awesome would that be, rowing truck gears and crawling around in a 5:1 or 6:1 granny gear with the 4:1 Rock-Trac? Then again, I'm assuming the Rock-trac will work with either. I would need adapters, a different shaft or, most likely, a different transfer case altogether. I haven't dug that deep into it, just recalling the LS/16L80 swap in my JKU. I had to go with an aftermarket NP transfer case for that swap.

And then there are the axle considerations with all that torque on tap with no converter to manage it... oh man, it get's really deep very fast. That's why Stellantis should give us the opportunity to order what we want; get it right from the factory to begin with.
Well the 4500 was optioned behind some early Hemi blocks in Ram 2500 trucks before they stopped offering them. And if we are dreaming might as well go with an atlas case or a 3 spd stak box. Or whoever is making them these days.
 

onepoundjeep

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love the info in this thread. I hadnt had MT is 15 yrs and was itching for one. after test driving it I knew I had to have it. I think removing the spring or the Act softer spring definitely helps.

all are correct on issues, but I still dont care (1st world problems), I would never pick AT. I got 33s and 3.45 gearing, its a dog, but its also a jeep not a sports car.

I debate regearing, I wanna test drive rubicon to see the difference it would make.

if i could get a centerforce clutch with guarenteed no issues I think I would do that if anything tho.
 

azwjowner

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I debate regearing, I wanna test drive rubicon to see the difference it would make.
I have 4.56 and 32s and it's transformative.

Also, I'm glad to read all the comments in this thread about how awful it is to learn the clutch. My JL is my first manual car -- I had it shipped from Mark Dodge and then taught myself how to drive around my neighborhood from YouTube tutorials. I had an awful time and stalled about 100 times, but glad to know I'm not uniquely stupid.
 

gato

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It's really simple.

Choice A: The absolute best automatic on the planet - ZF8 with 8 gears to keep you always in the power band.

Choice B: Possibly the worst manual implementation on the US market today. Defanging SW recalls, exploding clutch plates setting vehicles on fire, ridiculously bad gearing made worse the second you even think about putting bigger tires on.
 

alphawolff

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I have had 3. I love it when it works.

1. Purchased my 2018 JLU with 44,000 miles. Threw on 33's right away. Tried to teach my 15 year old a MT and he just couldn't make it work. The clutch was on or off.

2. Re-gear to 5.13's with 35's. He still really struggled to figure it out. 64k Miles

3. CF's second try at a JL Clutch - CFII - External Slave - 65k miles. It worked amazing. Totally different than stock. Feathering great. Moab Trip. My son figured it out instantly. Didn't pay much attention to cleaning the input shaft spline / probably added too much grease.

4. With 10k Miles on it, clutch started acting up. Hard to get it into 1st and reverse. Accidentally filled the bell housing with mud and destroyed the rest of the clutch.

5. Cleaned out the clutch, and while waiting for a new clutch, put the old one back together. Clutch worked again and shifted great. (cleaned input spline)

6. A week later installed a new CF clutch (same one) but with Internal Slave. Very small amount of grease on input shaft. LOVE the feeling of the internal. Easy press. Easy bleed. Used this setup for 30k miles. Started to not like 1st. Started to get stuck in gear when I started the engine.

7. At 105,000 replaced the clutch. This time CF said no lube on the spline. Its pre-lubed with a dry lube. Super cleaned the spline. Love the performance again. Sitting at 5000 miles on new clutch. Hoping for the best
Lol, I had to do a double take. 3 clutches in 100k miles is crazy. Talk about a love hate relationship
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