I'm just about to finish my clutch job. I need to repack the pilot and release bearings. What grease should I use , and should I get anything else while I'm at the store?

 

Any high temperature bearing grease for the pilot bearing(specification--NLGI-2).
The release bearing cannot be repacked(at least if it is a Mazda bearing).You can lubricate the release fork and parts of the release bearing.Molybdenum disulphide grease is typically used.

 

Use wheel bearing. Its high temp, It will work just fine.