I swapped a T-56 into my car probably 25K miles ago. I hammed the pilot bushing in, it was so tight the face was mushroomed probably 1/30" when I removed it a couple of months ago. It was mushroomed out, not in towards the shaft. I think all the hammering probably warped the bushing or caused some type of problem for it, because it started making noise at about 15K miles. No problem, I was about to take the tranny out anyway. When I got the bushing out, probably 1/16" had been eaten away by the input shaft. I inspected the input shaft, it was a little dark where it had been touching the bushing, but not scored. The soft brass shouldn't be able to wear the hardened shaft anyway. The guy who rebuilt my tranny (he is a local guy who has rebuilt quite a few T-56s) said the endplay was less than the endplay in most T-56s. We replaced the output shaft race, but not the bearing.

So I replace the pilot bushing again before installing the tranny. This time I sanded down the outer surface of the bushing and froze it before I put it in...when in fairly easy, no marks at all on the face or inner surface. I thought it was in right this time, & would be OK for a long time. About 2-3 weeks after I replaced the bushing, it started making noise again. I'm going to pull it out in a couple of weeks. What would cause the bushing to wear so fast? I did lube the bushing/input shaft both times before I installed the tranny. This is the brass pilot bushing from AutoZone...not the bearing.

 

Anybody?

 

Is it possible your tranning shaft is bent?

 

That would be my guess. The pilot bushing isn't really something that should be going out like that, something is causing it, my guess would be input shaft being bent.

 

How do you bend a input shaft???

 

I'm wondering the same thing, I think it would be difficult or impossible to bend the hardened input shaft without breaking it. It was fine for several months when I first put the tranny in, so I think it was fine when I got it. My car is only making 300RWHP on a good day, & I've never run slicks or DRs, I don't think I could either bend or break it.

 

ive heard of this being common when people do swaps. dont ask me why. but i talked to a local clutch place and all they do is make clutches. and he said that people that this happens to theres a couple of things that cause it. one a bent input shaft, and he said one way to for sure tell if this is it is to see if the clutch is prematurly wearing becuase if the input shaft is bent the clutch will slide around even with the pressure of the pressure plate thus cuasing the clutch to wear fast as well as the pilot bearing.

second is the bell housing milled wrong or there is something not letting the bell housing set to the rear of the engine or between the bell housing and tranny not letting it seat. so maybe the bottom is kicked out of line with the engine thus the input shaft not with the engine and there is the rear occasion that the place the "say napa" buys there parts from made a bad batch of bushing that the hole was milled out of square.

i think yours is the second or third choice.

let us know how it comes out.

 

You have to make sure that the tranny is situated properly... that's the only thing I can think of because the pilot bushing is basically the support for the input side of the tranny.

 

I could understand if it was dropped off a jack but as far as the other responces go...........mmmmmm, okay

 

Sometimes when taking the trans out people just don't support the weight of the trans. In others, if you have a couple of guys holding on to the trans as your trying to pull it out from the motor and you don't keep it in line with the motor as your pulling in out or sometimes you need to let go of trans to repostion your grip, the weight of the trans is on the shaft that's still in the motor. Thus you risk bending the shaft very slightly. You will not notice this by looking at because it's so slight, but enough to cause your pilot bearing to wear faster.

Scott

 

Jesus, what f****in hillbilly would do that??? Then again, nothing really suprises me. Might blow my mind cause its common sense not to do that, but suprise me? No!

 

Hey Steve, the fact that you're using a brass bushing... that's the problem right there. While parts stores list a bushing as an "alternative", GM uses a roller bearing.

Made short, put a roller bearing in there and you'll be a-okay . I too tried the brass bushing, after I had been told the factory roller bearing adds to some of the noise that is commonplace w/ T56's... and it actually scarred my input shaft.. Polished the marks out and put a roller bearing in there. It's been fine ever since. Just be sure when you install it you don't scar the face of it up. You can use the "ball" side of a ball peen hammer and then hit it w/ another hammer do drive it into the back of the crank.


Hope this helps.

 

Hey Shawn, how did you polish the input shaft? When you were using the brass bushing, did the shaft actually eat into the bushing? Mine is actually cutting into the bushing.

Scott, you would have to have a LOT more force on the shaft than just the weight of the tranny to bend the shaft. If it was that soft, it would twist in half the first time you put the peddle to the floor.

 

I know that aint my chat dog Steve Ricer

 

Hey Antz, whats up? Long time, no see...