driveshaft rubbing against trans after diff swap

[SketchyRollin564]

About two weeks ago i put a j30 vlsd in my s13. From what ive read up, and from past experience with my last 240, even though the j30 diff is about half an inch longer due to the abs sensor, and the abs driveshaft is half an inch shorter to compensate, you are still able to put the abs diff in without changing the driveshaft, and without any isssues. The driveshaft just slides the extra half inch into the transmission and it "should be fine"

however on this car it wasnt that easy. To begin with, after bolting the diff in, trying to get the back end of the driveshaft to meet with the diff was a pain in the a**. I had to wedge it in there with a flat head and a hammer. Then once it was in and drove away, everything seemed fine

It started off being that some smoke would start to come out of the shifter / ashtray area once i would get to above 85mph or so on the highway, but it wouldnt make any wierd noises and the smoke would go away once i would slow down to 75 or lower. I figured it was because i used a crap ton of RTV to fix an exhaust gasket leak down there while i swapped the diff, and that it was no big deal and would burn off. I figured it only smoked at higher speed cause that whole area would get hotter

came last night, i was on the highway driving to my friends shop to change an axle that had a messed up boot. The driveshaft/transmission area started making this annoying a** noise while i was driving. No it was not gear whine. Smoke would start to come out of the shifter area as low as 75mph, and a LOT of it. This time the smoke would smell and make me want to pass out. I slowed down to about 50mph the rest of the way there with my head out the window, and it didnt stop smoking. Once i arrived to the shop and shut the car off, there was still smoke coming out... what the crap?

got the car up on the lift, changed the axle, and put the car in 1st gear while it was up there to see what was up. We noticed that the end of the driveshaft was rubbing up against that big metal ring that goes around the tail shaft of the transmission rear main seal is, that must be why it gets so hot and why i smokes. Also noticed that while it was moving, the transmission was shaking from left to right... this is not normal, no? Keep in mind i have nismo motor mounts and transmission mounts that are on tight, so that eliminates the possibility of my mounts being bad

Before we could further look at it, i had to get the car off the lift to make room for the s15 coming in. They have to go to SEMA for the next week or so, so i dont really have another chance to get it up on the lift and further look at it. I also live in an apartment and dont have a garage or jack stands where i could put the car up myself and look at it... so im in a pickle here

Does anyone have any ideas what the hell could be going on?

[krash]

Couple of things.

Do you have an ABS driveshaft in the car right now?
Do you have an s14 trans in the car right now?

[SketchyRollin564]

Nope, i have a regular non ABS driveshaft. I know you "supposed" to use the ABS driveshaft, but ive done tons of research, and 98% of people who put in a j30 in their non-ABS 240, keep their old driveshaft and dont have any issues. This includes me on my last 240, which was an s14

Im not sure which KA transmission i have, s14 or s13, but i know its a KA transmission on an SR20 bellhousing (cause i have an sr20)

Also ill include this. From 10mph to about 25, the transmission shakes violently, after that it stops. After about 45mph it begins to smoke, and the fumes make me naucious. There is a possiblity that the transmission fluid is so low, that it gets hot enough that whatever little fluid is left will smoke, but that still doesnt explain the noise, or the left to right shaking at 10mph

[OutToWinPAHC]

burning out the tail shaft seal.... Or carrier bearing.... Remove and inspect

[SketchyRollin564]

burning out the tail shaft seal.... Or carrier bearing.... Remove and inspect

Tail shaft seal, maybe, since the driveshaft is being pushed forward from the extra legnth of the diff, but it only appears to be leaking from the shifter hole (missing C-clip, and gasket is non existant). However that really annoying noise SEEMS to be that the driveshaft is rubbing agains that metal circle thing, which appears to be there for the purpose of protecting the seal

carrier bearing sounds like it might be more likely... which would explain the left to right shaking, but wouldnt explain the noise, or the smoke... possibly a combination of both?

It possible to replace the carrier bearing if bad, without changing that piece of the driveshaft? It seems like its attached, but i dont know

The only reason i dont want to put in the ABS driveshaft, is cause the only one i can find around here, the guy wants $100 for. Thats money i dont have, and driveshafts usually go for about $40 around here. That, and i dont know for sure if that would fix the problem, it could be another issue, something stupid


Either way i cant drive the car more than 15 minutes at a time without feeling like im gonna pass out, so i wanna fix this asap. Im trying to convince them to let me get the car on the lift for half an hour before the end of the weekend so i can see whats going on

[krash]

Why don't you just get an ABS driveshaft? shorter, seems like it would solve your problems.

[SketchyRollin564]

burning out the tail shaft seal.... Or carrier bearing.... Remove and inspect

The only reason i dont want to put in the ABS driveshaft, is cause the only one i can find around here, the guy wants $100 for. Thats money i dont have, and driveshafts usually go for about $40 around here. That, and i dont know for sure if that would fix the problem, it could be another issue, something stupid

Cause of that, lol. Im only going to get it if i absolutley have to, otherwise theres more important things i need my money for right now.

Im putting the car up on the lift again today, we're gonna take a closer look at things. First thing im going to check is if the carrier bearing is bolted in all the way/came loose, and if its still good. If thats good, then we're going to try and take off that metal ring, or cut off half of it.. whatever we have to do

If that seems to solve our problems, then im going to just remove the shifter plate, make a gasket with some gasket maker, fill her up with some fresh gear oil, pop the shifter back in WITH a C clip this time... and that should be it

however, since its my car... its never that simple lol. Ill post back and let you know what happens

[240life]

I have had to remove the ring (dust shield) on the back of the transmission after swapping bell housings onto a USDM rear section in order to make room for my one piece,..this may be what is needed to fix your problem.

[SketchyRollin564]

Well we removed that metal ring and that noise stopped. We drained the transmission fluid, filled it up to the proper level, sealed the shifter plate properly and put a C clip to hold it in and the smokes stopped. We took off the carrier bearing (and driveshaft) and when we put it back in the shaking stopped for the most part, but still wobbled a little

Heres what we noticed. The passenger wheel wobbled a little bit. We followed the axle to the diff, and you could see that the output shaft was not spinning straight, and wobbling a little bit. The drivers side however, was fine. My guess is that when the axle blew and the whole rear end went from 50mph to 0mph and hopped to a stop, it put a lot of stress on it and messed that output shaft off. Will most likely just replace the diff.

However, heres the wierd part. The output shaft or whatever its called in the front of the diff seems to spin straight. However the rear section of the driveshaft seemed to wobble more than the front (which has the carrier bearing). With the driveshaft completley out, looking at that main gear the driveshaft grabs on to, with the car in every gear at all different speeds, that gear/shaft spun completely straight and didnt wobble at all. The transmission only moves around with the car in gear if the driveshaft is connected. Does this mean the driveshaft itself got bent/torqued/warped when the rear end just froze from the axle taking a crap on me?

I am definatley replacing the diff with a low milage j30 vlsd from a junkyard that ill pull myself. Id rather just do that than deal with changing the output shaft and having the problem potentially still exist

However, i dont want to have to change the driveshaft if i dont have to. Is it possible that the passenger output shaft is causing the driveshaft to wobble a little and that the driveshaft is fine? Or, is it also possible that just the rear section of the driveshaft is a little bent?

The less stuff i have to replace the less money i have to spend. And the less work... however changing the driveshaft as a whole would be a lot quicker and easyer, i have a friend with a 5speed driveshaft laying around with a bad carrier bearing, so i could grab just the rear section and see what happens

[salvadorss09]

did u ever figure out what was the solution? abs driveshaft?
i have that same problem and i think swapping my driveshaft for a abs on it will fix this