Pilot Bearing
 

I was getting a slight vibration when i was driving in all gears. I can feel the vibration more in 4th gear of my Tremec 3550. The performance place said it could be the pilot bearing because 4th gear is actually the input shaft. So anyways i asked him how you could tell if you need a new one? He said lets look at the old T-5 that i broke 2nd gear. Which he had posession of. We looked at it and there was a wear and tear on the input shaft. So i went a bought a new pilot bearing yesterday. Now i am done taking out the transmission and clutch, and i find something very odd.......there is no pilot bearing in there!!!! I guess it never had one installed. I started to laugh... But now i am wondering what are the main uses for the bearing to just supply some support to the transmission or something more? If anyone can help please.
Thanx

Cody

No pilot bearing!!! That can't be good.
I believe the main reason is to support that end of the input shaft but also to align the shaft to the crank. I hope you have not damaged anything by running without it. The vibration you mentioned was probably putting your tranny through more abuse than it should normaly see.

SilverSN95 is right...the pilot bearing aligns the input shaft to the crank. Without it you can get very bad wear patterns on the input shaft, input bearing, input race and the input gear/main gear mesh in the transmission.

How long were you driving it like this? I think you should open up the trans and look at it or have the shop do it. Not to mention that may have beat your crank bearings as well...

Whoever installed the transmission should have put a new pilot bearing in. It sounds like that shop did the install because they have your old T-5, right?

Whoever forgot to install it should be responsible for fixing it.

Good luck,

Rich D.