Clutch / Transmission Question

[Jeme]

2003 Wrangler 4.0L NV3550 5 Speed 158,000 miles - this jeep is new to me so not much on the history..

Heard a weird sound upon starting the car on Sunday, Jeep will no longer go into gear. The Jeep will smoothly shift through all 5 gears and reverse when the engine is off. Thinking this is a clutch problem.

Other than the flywheel and Master cylinder is there anything else I should change at this time. Going to use a LUK clutch and a Sachs metal throw out bearing, because of the plastic in the LUK? I have heard that is the correct way to do it?

Finally I run REdline MTL fluid and the first time I changed it I thought I was panning for gold -lot of shinny dust in the transmission fluid.

Here is the real questions - the car shifts fine when it was working, third gear might be a little crunchy. Since I am doing all this label do I change the transmission now as well?

Any advice here - I am a noobie. Thanks in advance.

 

[JMT]

Change the clutch.

If it gets to needing a new transmission you’ll want to swap to an AX-15. They still manufacture brand new ones.

 

[Jeme]

Change the clutch.

If it gets to needing a new transmission you’ll want to swap to an AX-15. They still manufacture brand new ones.

Thanks, I have heard that - what is required for the swap? How long should a transmission last? My Jeep is bone stock and I do not think it has ever been wheeled, still had and the stock suspension parts on it when I got it. Thanks!

 

[MikekiM]

Legend has it that LUK switched to the nylon/plastic TOB so that it does less damage if/when the TOB fails. No idea whether it's truth or legend. I just swapped out a National TOB that failed within eight months of being replaced.

Thanks, I have heard that - what is required for the swap? How long should a transmission last? My Jeep is bone stock and I do not think it has ever been wheeled, still had and the stock suspension parts on it when I got it. Thanks!

I have a very mild build that I daily drive. NV3550 died around 100k-ish.

The AX15 is completely bolt in and uses all the parts associated with the NV3550. Three exceptions... the reverse light harness may be too short. It's located on the opposite side of the transmission. Novak sells a pigtail for $20. I ordered it but didn't need it. The transmission mount may need to be modified to clear two bolt heads, or again you can order an adjustable from Novak, which I did and didn't need. Last, there is a threaded bung on the AX15 that doesn't play nice with some transfer case shifter cable mounts. Requires either the bung be removed or the mount be clearance. I clearance the shifter cables mount.

 

[Jeme]

Legend has it that LUK switched to the nylon/plastic TOB so that it does less damage if/when the TOB fails. No idea whether it's truth or legend. I just swapped out a National TOB that failed within eight months of being replaced.

I have a very mild build that I daily drive. NV3550 died around 100k-ish.

The AX15 is completely bolt in and uses all the parts associated with the NV3550. Three exceptions... the reverse light harness may be too short. It's located on the opposite side of the transmission. Novak sells a pigtail for $20. I ordered it but didn't need it. The transmission mount may need to be modified to clear two bolt heads, or again you can order an adjustable from Novak, which I did and didn't need. Last, there is a threaded bung on the AX15 that doesn't play nice with some transfer case shifter cable mounts. Requires either the bung be removed or the mount be clearance. I clearance the shifter cables mount.

Thanks so much for your insight. So the AX-15 is the way to go? Is there any thing you need to do to the ECM or does it just recognize the new transmission?

Finally if I am not having issues with my transmission now - no need to replace just keep rolling. 158K miles.

 

[Rickyd]

How does the clutch pedal feel? Different that before the weird sound?

 

[Jeme]

How does the clutch pedal feel? Different that before the weird sound?

No still feels fine, when the engine if off I can shift through all the gears fine.

 

[lBasket]

No still feels fine, when the engine if off I can shift through all the gears fine.

Your clutch doesn't come into play when the engine is off, you can row gears when off with a failed clutch system

 

[Jeme]

Your clutch doesn't come into play when the engine is off, you can row gears when off with a failed clutch system

Correct but it may indicate that the issue is with the clutch and not the transmission?

 

[cb4017]

My 05 was making weird noises related to the clutch pedal. I figured throw out bearing. To old to be laying under vehicles now days so I took it to a local Driveline and Gear Service place. He recommended LUK and he did the whole works for $925. TOB, pilot bearing, pressure plate and friction disk.
All better now.

 

[Jeme]

That is a great price - I am probably going to be $900 + Parts.

 

[cb4017]

That is a great price - I am probably going to be $900 + Parts.

I thought so too. Good enough I dropped off a case of beer for the crew later on the day I picked it up.

 

[MikekiM]

Thanks so much for your insight. So the AX-15 is the way to go? Is there any thing you need to do to the ECM or does it just recognize the new transmission?

Finally if I am not having issues with my transmission now - no need to replace just keep rolling. 158K miles.

As far as a replacement for a failed/failing NV3550? My research led me to the new Novak AX15. Not the cheapest option for sure, but if you're going to keep the Jeep and have the money it's likely your best option. Bolt it up and drive. No electronic wizardry needed.