I pulled the passenger side axle today because I was going to tryout the 3.91's that failed on me at Englishtown last year. Dan could not find anything wrong with the center section so I was going to try them again. Well I pulled the axle out because he had heard around that some axle manufacturers were having trouble with splines shearing off when used with green bearings (I am using green bearings) and older 8 3/4 rears. Apparently the older style sure grips have 2 sets of teeth that have to be lined up to get the axle in and mine only has one. With green bearings the axles don't fully engage the inner set of teeth and the tip of the axle gets the splines sheared off. My axle has about 1/8" of the splines gone on the end
.I guess I am going to run my 3.23's at Englishtown and settle for not getting into the 15's