Transmission Pilot Bushing

[bruce11495]

Re : Roller bearing ....NOT

Just rebuilt my engine and talking to the machinist I happened to mention this. He's an ex-crewchief on a drag racing team. He was adamant about not using the roller. He said he has seen them seize and take the input shaft/ clutch out of a car MORE than once!! Was enough convincing for me....

[Joe L.]

Re: Re : Roller bearing ....NOT

bruce-----

With the roller pilot bearing, bellhousing and transmission alignment are much more critical than with the oilite bronze bushing. The roller bearing will not "wear in" to correct for minor mis-alignment. It must be right from the "get go". If the alignment is right, the roller bearing should never be a problem. If the alignment does not fall within a very narrow range, one could end up with the type of problems you described. How do you confirm if your bellhousing and transmission alignment is right? It involves procedures and measurements that few folks ever get involved with.

[bruce11495]

Re: Re : Roller bearing ....NOT

Joe....Enough said, I rest my case. They didn't come off the production line with that tight a tolerence. The part was strictly designed for the racing side where this would be addressed.....

[Robert D.]

Re: Re : Roller bearing ....NOT

i have spoken to alot of people about roller bearings or not and the concensus is not to use roller bearings because they do fail more often and they do take alot of things with them i went with bronze and have no problem the only advice i give when installing it is check the size and dont bang it in with a hammer use an old input shaft because if you mushroom the inside hole then the trans wont slide in properly

[Peter Cipriani]

Re: poor quality pilot bushings

If you check the new pilot bearings with a magnet you will see that they are magnetic. They must have a lot of steel in them. The old style pilot bearings are bronze. Steel on steel will squeal like a pig!! I purchased the real bronze type from a guy in Carlisle. I think his name was Ed Hartnett? He claims all the new bearings are offshore crap!!

I hope this helps. Peter

[John H.]

Re: Re : Roller bearing ....NOT

I've used the GM needle roller pilot bearing (the same part is also re-packaged and sold by Moroso and others) in about six cars over the last ten years, and have had no problems with any of them. Regardless of the bushing-vs.-bearing usage, I always use a dial indicator setup to ensure that the bellhousing opening is concentric with the crank; I've never had a stock bellhousing check out of spec, but EVERY time I've used a Lakewood bellhousing I've had to use various combinations of Tavia offset dowels to bring the Lakewoods into spec.

[Dennis C.]

Re: Re : Roller bearing ....NOT

John... I suspect there is considerable experience, insight, knowledge and truth in your post. As a semi-unrelated aside, the needle bearing item, I belive, was the Gereral's HD application part.

[Terry M.]

Re: Re : Roller bearing ....NOT *TL*

There are hundreds of thousands of HD trucks using the pilot bearing without all the doom and gloom some attribute to this part. I guess I must be missing something.

[John H.]

Re: Re : Roller bearing ....NOT

I don't understand the "doom and gloom" either; this part was designed and released specifically for use with manual transmission diesel-engined trucks (read durability) - those buyers DON'T appreciate having to take their truck out of revenue-producing service and tear something down to replace a $10.00 part before they see 250,000 miles. Verifying concentricity between the crank and the bellhousing opening (and correcting it, if necessary) before installing the transmission is standard practice when building a race car, and (IMO) is simple common sense for a Corvette; always has been for me, anyway.