mtwoolford

I think its just surface oxidation; if the splines aren't worn or deformed , I'd clean it with a wire wheel on the end of a drill chuck and call it good; I would be careful about getting anything up in the collar which could impact the front seal.

I don't want to open a huge debate but I always use some anti seize on the splines, even when you slide the new clutch disc onto the input shaft and wipe away any visable excess several time, there will still be a very thin layer, maybe not even visable to the eye which will remain adhering to the metal (unless it's removed with some sort of solvent).

again, for what its worth, if available, I prefer to use a clutch disc with a metallic facing (bronze, copper, iron etc) rather than an organic facing; they seem much more tolerant of contamination, and if what I've read is true, the coefficient of friction for metallic discs goes up with temperature, just the opposite of organic discs.

mtwoolford

what aftermarket bellhousing?

mtwoolford

If the intent of you thread is to check (amongst other things) the throw out bearing; be aware that the early "black tag" ZF's use a different throwout bearing than the later "blue tag" ZF's. They LOOK the same, but the early one's i.d. is larger than the later ones and an early one will install, but not operate properly on a later transmission (but not the other way around) The early throwout bearings are often sleeved in the inside diameter with a plastic (nylon) insert to allow their use on a later trans.

MatthewMiller

No debate: I've done exactly one clutch job, so if others have more experience and did it differently, I'd defer.

oscarm98

I think this is exactly what is going on with my clutch!

Where would one find this nylon sleeve that you are talking about?

Thank you

Oscar

oscarm98

Okay so I went out and was able to measure my Throwout Bearing ID and the ZF guide tube OD today.

The ZF Guide Tube is 1.373" and the ID of the Throw out bearing measures about 1.392"

My question is what is the part number of the "Larger" (smaller TOB is 1.307") throwout Bearing? and where to get it.

Should I replace it since I am in there and it looks like there is .019" of gap (not sure what the tolerance is supposed to be)

Thank you guys

Oscar

mtwoolford

the "large" throwout bearing, 1992-1993 (and earlier ZF 6 speeds fitted to L98 engines): GM part number 10203567

the "smaller" throwout bearing 1994 - 1996; GM part number 10222087

Go to Corvette Central's web site and enlarge the photo's of their item #534291, which is for 1994-1996, and it will show pretty clearly the plastic / nylon bushing installed in the i.d. of the throwout bearing; compare to item 534248