2005 TJ NSG370 transmission rebuild / replacement options

What type of vibration is it? Is it just in the shifter, or the entire Jeep is shaking? Is it oscillating dependent on speed?

entire jeep but I can feel it most in the shifter, pedal, and under my seat. Coasting is pretty decent but whenever I hit the gas it's terrible.
Another thing I just remembered from when it had to be front wheel drive for a moment when the Dana 35 exploded and broke the yoke off the transfer case initially is that, although the vibration was the same before and after, when I only had the front shaft in and in 4 high, the vibration wasn't nearly as bad but holy crap if the front pancake locker didn't make it terrible to control! Either way, 30 mph is the limit either way but I did get it up to 70 once on the test drive and I guess the engine was working so hard it overheated and split the top of the radiator where it normally happens. Whether that is age, my gauge is stuck on 213 when it heats up, or there's a massive cooling system blockage I do not know.

Oh and good grief, this is an extremely important detail that I failed to mention up front:
I had it regeared to .456 and went from 33"s to 35"s and within a couple months the vibration started. It has about 130k miles on it.
 
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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?

Oh, bro. It doesn't and I didn't! But the marbles sound coming from behind the engine is kind of telltale for a broken pinion bearing. But the pinion angle has to be trued 100%!!! Thank you for the question! I plan on taking this TJ to my grave but I need an in-town daily driver as soon as I can get it stabilized. 8mpg sucks lol
 
Oh, bro. It doesn't and I didn't! But the marbles sound coming from behind the engine is kind of telltale for a broken pinion bearing. But the pinion angle has to be trued 100%!!! Thank you for the question! I plan on taking this TJ to my grave but I need an in-town daily driver as soon as I can get it stabilized. 8mpg sucks lol

Well, obviously you have driveline vibrations. You have to raise the pinion. You need adjustable rear control arms to do this. Your angle of pinion should start at -1* relative to the angle of the driveshaft.
IMG_9376.webp
 
entire jeep but I can feel it most in the shifter, pedal, and under my seat. Coasting is pretty decent but whenever I hit the gas it's terrible.
Another thing I just remembered from when it had to be front wheel drive for a moment when the Dana 35 exploded and broke the yoke off the transfer case initially is that, although the vibration was the same before and after, when I only had the front shaft in and in 4 high, the vibration wasn't nearly as bad but holy crap if the front pancake locker didn't make it terrible to control! Either way, 30 mph is the limit either way but I did get it up to 70 once on the test drive and I guess the engine was working so hard it overheated and split the top of the radiator where it normally happens. Whether that is age, my gauge is stuck on 213 when it heats up, or there's a massive cooling system blockage I do not know.

Oh and good grief, this is an extremely important detail that I failed to mention up front:
I had it regeared to .456 and went from 33"s to 35"s and within a couple months the vibration started. It has about 130k miles on it.

With the marble sound you're hearing, does it happen only at idle? Is it with the clutch pedal up or down?
 
What type of vibration is it? Is it just in the shifter, or the entire Jeep is shaking? Is it oscillating dependent on speed?

It oscillated a bit before the rearend exploded — the carrier literally shattered into 3 pieces, broke the pin in half, and threw the gears into the cover and poked numerous holes in it. I'll grab some pictures for the need for warporn tomorrow and post them. After replacing everything behind the transmission, it doesn't oscillate but vibrates harder and harder when accelerating and the faster it goes, the worse it gets. It feels a lot like a failed u-joint would but they are brand new and came mounted on the Tom Wood driveshaft. I thought it was Adams but was mistaken.
I'm intrigued by the comment about the pinion angle of the pineapple but since the vibration pattern at the root is unchanged between the stock Dana 35 and the used Dana 44 from an LJ is the same, I don't think that's a contributing factor...although it is a very important item that will need to be addressed before getting serious again.
 
Well, 12, but yeah, sucks gas. Have to adjust to the Smiles Per Gallon mentality.

It wasn't always so terrible.. was 12 on average, sometimes 13. Once the vibration started it went down to 9, then 8, then 7, then who knows when it's zero miles across the board. :D
 
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Well, obviously you have driveline vibrations. You have to raise the pinion. You need adjustable rear control arms to do this. Your angle of pinion should start at -1* relative to the angle of the driveshaft.View attachment 694457

I watched a video on how to do this and plan to do it but the symptom and vibration is EXACTLY the same as before. I'd love to hear about any shortcuts in the math because I'm visual, not a calculator type guy. This is wonderful and the 2nd illustration is where it's at. I gotta say, SYE is the way to go! The dana 44... I don't know the term but it is definitely closer to the t-case and this is something I can do next weekend. I also need some advice on clearing out the engine coolant passages and confirmation of whether an OEM radiator is truly the best option for replacing the failed on in there now.
I think it is worse than before and extremely likely to what JMT brought up about the rearend angle. It needs to match figure #1 of his illustration.
 
My responses will be hit or miss over the next few days but holy shit I love you guys. Thank you SO MUCH thus far. I thought my Harleys were cool until picking up the TJ 4 years ago and selling both of them within 6 months. Hate to see beautiful American steel wasting away so they went to a badass new owner--a lifelong friend that became a stud in a couple Texas chapters of the Boozefighters. Props to you, my man!
 
With the marble sound you're hearing, does it happen only at idle? Is it with the clutch pedal up or down?

Actually, I didn't read your question properly and answered incorrectly. The marble sound doesn't happen if I start it daily. It only happens after sitting for a few days and after starting in neutral, with the parking brake engaged, for about 20 seconds and then gets quiet. I thought at first it was a main bearing or something that sheared in the engine. Giving it gas makes the noise go away more quickly but I've only tried that twice because I realized it could compound the issue. I didn't dare to put it in gear and let out the clutch, out of fear!
Something I can try on Thursday is taking out the rear driveshaft and putting only the front back in, shifting to 4h, and giving it another test drive. Thoughts?
 
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Actually, I didn't read your question properly and answered incorrectly. The marble sound doesn't happen if I start it daily. It only happens after sitting for a few days and after starting in neutral, with the parking brake engaged, for about 20 seconds and then gets quiet. I thought at first it was a main bearing or something that sheared in the engine. Giving it gas makes the noise go away more quickly but I've only tried that twice because I realized it could compound the issue. I didn't dare to put it in gear and let out the clutch, out of fear!
Something I can try on Thursday is taking out the rear driveshaft and putting only the front back in, shifting to 4h, and giving it another test drive. Thoughts?

ok if it's not doing it all the time then I think the pilot bearing is not the main issue. What happened with the rear end? Are you sure you're running the same gears in the front and rear? Also check the transmission mount. Im sure thats not the main issue, but if the transmission is shaking through the shifter that could be bad as well. If it's driving as poorly as you're saying I think it might be best to try and diagnose the issue(s) first since driving it will probably cause more damage.
 
I watched a video on how to do this and plan to do it but the symptom and vibration is EXACTLY the same as before. I'd love to hear about any shortcuts in the math because I'm visual, not a calculator type guy. This is wonderful and the 2nd illustration is where it's at. I gotta say, SYE is the way to go! The dana 44... I don't know the term but it is definitely closer to the t-case and this is something I can do next weekend. I also need some advice on clearing out the engine coolant passages and confirmation of whether an OEM radiator is truly the best option for replacing the failed on in there now.
I think it is worse than before and extremely likely to what JMT brought up about the rearend angle. It needs to match figure #1 of his illustration.

You just need some adjustable rear control arms, an angle finder, and a little time.

You mentioned in your original post that you already have an SYE and you mentioned that you have a custom rear driveshaft from Adams.

You also mentioned that you now have a Dana 44. Its snout is about 1/2-3/4” longer than the Dana 35 snout, but you have a new shaft I’m assuming is the proper length for your setup.

With the SYE all you really need to do is get adjustable rear control arms. Double adjustable are much easier to adjust since you can do it with the Jeep on the ground and you don’t have to remove the bolt on either end of the control arm and fiddle with jacks to adjust the pinion angle of the differential snout. Much, much easier with double adjustable. From there you can just adjust the arms to raise the pinion. You’ll use your angle finder to measure the angle of the pinion and the angle of the shaft. When the pinion is 1* lower than the shaft you’ll give it a spin and see how your vibes are then. If you still have them you’ll make minor adjustments trying 0* (equal) or 2* lower, etc… When the vibrations are gone your done.

It won’t hurt to remove that rear driveshaft to confirm it’s the improper operating angles of the rear shaft. Report back.

And I agree with @SentientMachinery that your transmission mount could be worn out. Not convinced that’s the main issue, but it can be a contributing factor.
 
You just need some adjustable rear control arms, an angle finder, and a little time.

You mentioned in your original post that you already have an SYE and you mentioned that you have a custom rear driveshaft from Adams.

You also mentioned that you now have a Dana 44. Its snout is about 1/2-3/4” longer than the Dana 35 snout, but you have a new shaft I’m assuming is the proper length for your setup.

With the SYE all you really need to do is get adjustable rear control arms. Double adjustable are much easier to adjust since you can do it with the Jeep on the ground and you don’t have to remove the bolt on either end of the control arm and fiddle with jacks to adjust the pinion angle of the differential snout. Much, much easier with double adjustable. From there you can just adjust the arms to raise the pinion. You’ll use your angle finder to measure the angle of the pinion and the angle of the shaft. When the pinion is 1* lower than the shaft you’ll give it a spin and see how your vibes are then. If you still have them you’ll make minor adjustments trying 0* (equal) or 2* lower, etc… When the vibrations are gone your done.

It won’t hurt to remove that rear driveshaft to confirm it’s the improper operating angles of the rear shaft. Report back.

And I agree with @SentientMachinery that your transmission mount could be worn out. Not convinced that’s the main issue, but it can be a contributing factor.

Wren from Wrenegade Jeeps near Wichita Falls, TX is my expert and where I buy used parts from. He did the math for the driveshaft length and I trust him. However, he likely knows that a critical step is lining up the pinion angle but it's so obvious to him he didn't think about telling me. I'm an IT guy and I make a lot of assumptions just like that regarding what I assume they know and it took years for me to understand that I need to document every step because not everyone has the technical savvy to automatically know the gaps.
I won't have extra money until around July 19th but will order a transmission mount and both upper and lower control arms immediately following payday! The rubber on my trans mount looks ok but either way, I will order one since it will someday fail regardless and looks might very well be deceiving me!

So back to the driveshaft length. Could it be that the problem is the driveshaft is reaching the end of its length since the pinion angle is at the stock horizontal angle? I'm not sure about how the geometry works.
 
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You just need some adjustable rear control arms, an angle finder, and a little time.

You mentioned in your original post that you already have an SYE and you mentioned that you have a custom rear driveshaft from Adams.

You also mentioned that you now have a Dana 44. Its snout is about 1/2-3/4” longer than the Dana 35 snout, but you have a new shaft I’m assuming is the proper length for your setup.

With the SYE all you really need to do is get adjustable rear control arms. Double adjustable are much easier to adjust since you can do it with the Jeep on the ground and you don’t have to remove the bolt on either end of the control arm and fiddle with jacks to adjust the pinion angle of the differential snout. Much, much easier with double adjustable. From there you can just adjust the arms to raise the pinion. You’ll use your angle finder to measure the angle of the pinion and the angle of the shaft. When the pinion is 1* lower than the shaft you’ll give it a spin and see how your vibes are then. If you still have them you’ll make minor adjustments trying 0* (equal) or 2* lower, etc… When the vibrations are gone your done.

It won’t hurt to remove that rear driveshaft to confirm it’s the improper operating angles of the rear shaft. Report back.

And I agree with @SentientMachinery that your transmission mount could be worn out. Not convinced that’s the main issue, but it can be a contributing factor.

Hi JMT. I drove it with the rear driveshaft out and confirmed the vibration is pretty much gone. However, the small split along the top of the radiator was concerning enough to keep me from trying to get up past about 50. Since the rear driveshaft-only vibration starts getting severe around 20 MPH, I agree that setting the proper pinion angle along with a new trans mount is the next step. It even shifts into 2nd better when only front-wheel drive... don't have to finesse it unlike how I have to do with the rear driveshaft installed.

As far as double adjustable control arms. Can someone link me to what exactly I need? I'm obviously into affordable options but not Chinese Amazon/eBay junk.

I would have simply bought another TJ and used mine for parts but there is absolutely no trace of rust anywhere. Kind of priceless..
 
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Depends on how much you want to spend. Joint quality is at the center of that discussion. Most here will opt for Johnny Joints and those are in Savvy arms. Some like Metalcloak. Their Duroflex bushing is not my favorite design at all, but they get people by who don't stress their joints. Core 4x4 might have an affordable offering. I thought they had double adjustable, but I'm not seeing them. A few links:

https://savvyoffroad.com/products/savvy-7075-aluminum-jeep-tj-lj-control-arm-set-new-7075-series
https://core4x4.com/shop?vehicle=jeep-wrangler-tj-6&category=1
https://metalcloak.com/jeep-tj-lj-w...ries/tj-wrangler-suspension.html#subCategory0

You may just need the 4 rear control arms. Can't recall your situation entirely.
 
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I think I just need rear upper and lower control arms. I found these on Metalcloak's site and wonder if they would do:

https://metalcloak.com/aluminum-control-arms-double-adjustable-tj-lj-xj-upper-front.html - $329
https://metalcloak.com/aluminum-control-arms-double-adjustable-tj-lj-upper-rear.html - $349

The first link are "front" uppers, but the second link is correct for the "rear" uppers. Find the "rear" lowers and yes, those four rear arms would work to adjust your rear pinion. I've used the Metalcloak arms with Duroflex bushing and presently have a set of eight arms on one of my rigs. Most frown on them here because they are a steel ball with rubber bushing vulcanized to the ball, so when you articulate the rubber can pull off the ball. I never experienced this happening probably because I don't get enough opportunities to wheel, but I have seen it firsthand. I think they would work fine for your situation.