Something to do with the Factory assembly line I believe, Just filled / sealed with the windscreen "Dum Dum" at the Factory (can be a concern for leaks)
It’s just the cover that’s stripped. The diff itself I’m rebuilding with a 400lb spring and 22 plates and uprated output shafts. Will also tap the case for a cooler.What with the stripped threads I’m surprised you didn’t go for a HD diff from a Big block car?
Correct but GM had the bolt in caps for a reason. I too have a diff cooler set up.It’s just the cover that’s stripped. The diff itself I’m rebuilding with a 400lb spring and 22 plates and uprated output shafts. Will also tap the case for a cooler.
To my knowledge the only difference between big block and small block diffs is the output shafts.
If it was just a sump retainer I’d Helicoil but it’s a couple of the holes that hold the diff to the crossmember and therefore hold the suspension to the car, not worth the risk in my opinion. The rear cover isn’t too expensive anyway.
If it’s just leaks, it’s relative easy to change seals. Rebuild is a bit harder as you need to set the lash/tooth interface between the crown wheel and pinion. That requires use of a dial gauge, engineering blue and often multiple assembly/strip downs. Not hard if you follow the procedure but a bit of a faff.