2005 TJ NSG370 transmission rebuild / replacement options

interface

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Aubrey, TX
edit: I just found this thread and it has some good information: https://wranglertjforum.com/threads/nsg370-manual-transmission-replacement-options.38159/
Anyone have anything to add? What I need is affordability, future wheeling reliability, and simplistic installation options requiring simple mods or none at all. www.nsg370.com might be the answer... thoughts?


I have an '05 TJ X with an NSG370 trans. It has a vibration issue that I previously believed to be within the rear-end or transfer case. I upgraded the rear-end from a Dana 35 to a 44 out of an LJ and replaced the xfer case for one that already had the SYE installed. After those repairs and a test drive, the vibration was still present and I can only get up to about 20-30 mph before it gets pretty violent. The symptoms remind me of a failed pilot bearing and after sitting without starting it for a few weeks, it sounds like marbles rolling around within the bell housing.
My problem is that I can't find anyone locally in my small town in west Texas willing to even look at it. I know the most practical option is moving to an AX15 instead... but that's about all I know.

One of the main problems, of course, is limited funds due to providing full time care for my parents to keep them at home before the inevitable. Living two hours away and being a self-employed IT consultant has had a terrible impact on the amount of billable hours, causing my income to be cut by about 3/4 over the past 14 months.

With all of that said, I need to know my best options for saving money and, since I'll be doing as much of the work myself as possible, the most straightforward replacement options, such as an AX15 swap or any another route. I figured I'd ask the experts here and get some opinions and advice.

Thanks in advance!
Mark
 
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You need to find where the vibration is coming from. 20-30mph is not very fast to be getting what you describe as a "pretty violent" vibration. Having swapped rear axles and TCase it's unlikely to be there. What about your u-joints or centering yoke?
 
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There's no reason to resort to the parts canon to try to find a vibration. Find the vibration and fix it. If it is the transmission then fine, but these are $$$$$ parts to be throwing at a vibration.
 
You need to find where the vibration is coming from. 20-30mph is not very fast to be getting what you describe as a "pretty violent" vibration. Having swapped rear axles and TCase it's unlikely to be there. What about your u-joints or centering yoke?
I totally agree. The lack of a mechanic that is willing to look in my small rural town has been a big part of the issue. It can't be u-joints because I went from a slip yoke t-case to SYE with a customer driveshaft. I've tried both with and without the front driveshaft installed and it's the same. :(
I need someone smart to diagnose this before I throw good money after bad!
 

That's the same one that I have! The problem has been caring for my parents in the Dallas area while living out in Graham, TX two hours away where the jeep is. I haven't even had time to take out the trans due to an average of 25 days at my parents' and 5 days at home for over a year. It took 11 months of a day here and a day there to even swap the t-case and rearend, which should have taken max two days. I have destroyed shoulder joints so I move a lot slower than I used to, also.
Keep it coming, guys. This is great!!
 
I totally agree. The lack of a mechanic that is willing to look in my small rural town has been a big part of the issue. It can't be u-joints because I went from a slip yoke t-case to SYE with a customer driveshaft. I've tried both with and without the front driveshaft installed and it's the same. :(
I need someone smart to diagnose this before I throw good money after bad!

Have you tried removing the rear driveshaft? I know you said it’s new, but still. I had Adam’s rebuild my rear shaft and guess what, they didn’t replace a bad ujoint. I assumed the whole shaft was good. Found out 3 weeks later it was a ujoint.

There are good people here who can help diagnose.
 
I totally agree. The lack of a mechanic that is willing to look in my small rural town has been a big part of the issue. It can't be u-joints because I went from a slip yoke t-case to SYE with a customer driveshaft. I've tried both with and without the front driveshaft installed and it's the same. :(
I need someone smart to diagnose this before I throw good money after bad!

Have you tried removing the rear driveshaft and driving it in 4-High? That would implicate or rule out the rear drive shaft.
 
Have you tried removing the rear driveshaft and driving it in 4-High? That would implicate or rule out the rear drive shaft.

Everything behind the transmission is new or rebuilt. The front driveshaft is currently uninstalled so my guess is that would have to be either something with the engine, clutch/flywheel, or trans.
 
Have you tried removing the rear driveshaft? I know you said it’s new, but still. I had Adam’s rebuild my rear shaft and guess what, they didn’t replace a bad ujoint. I assumed the whole shaft was good. Found out 3 weeks later it was a ujoint.

There are good people here who can help diagnose.

It's a custom build Adam's end-to-end. :(
 
It's a custom build Adam's end-to-end. :(

It may be fine, just trying to rule it out. It’s an easy way to rule it out if you can get to the Jeep. Taking care of parents and all.
 
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Do you have adjustable control arms? Did you tilt the rear axle up when you switched to a double cardan driveshaft?
 
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What type of vibration is it? Is it just in the shifter, or the entire Jeep is shaking? Is it oscillating dependent on speed?