Sorry they weren't grade 5 they were grade 8. And 316 L is a type of hardness rating for stainless, They were just bolts and the part # would be a 1/2-20 X 1 1/2" bolt mine thread in not press in. How is it I see people with narrowed rear ends and a 15" wide slick driving around town not shearing studs. If your paying for this one I'll put another Detroit locker in. For now I'll work with what I got and try some ARP studs and maybe i'll be barrel rollin down the highway soon to put and end to my misery.

with a Detroit locker. All this said, I don't think your spool is the reason for your broken studs either but if you ride a lot on the street you should at least get a Detroit locker before you get yourself into trouble, especially if you get caught in the rain.
... So I will have a set of 31 splines stock size axles (4 lugs) + Strange A1090 c-clips (need new bearings) for sell if anyone is interested...