I have a 671 posi carrier and was told I could put a clutch pack from a corporate 8.5 posi. Is this true? Also could someone tell me what years the w27 option was available?

 

With the O-Axle only 1970 and then it was a special aluminum centered housing that was usually replaced under warranty due to it not being strong enough to hold the abuse put through it.

 

Yes,the clutch packs from the older style 8.5" 10-bolt posi units are the same.The ones with the "S" spring like what you have.These clutches are a knurled steel,& have square tabs on the ends.The clutches for the Eaton posis will NOT work. GM discontinued the clutches last year,but there are still some sources to get them.

 

Thanks Brian for the confirmation. Could you give me a couple of sources or do you have a set?

 

I bought a bunch from GM when there was word that they were stopping them,but I do not want to sell mine.I've talked with a few people that got them from DTS & a few other differential companies.Ratech also had them under part number RAT-1809,but I do not know if they still have them or not.Have you looked at your clutches yet.You might be able to retain your existing clutches,& just shim them tighter.They weren't assembled very aggressively back then,& usually have room for a bunch more shim.