Greg Linton's post about crush sleeves got me looking into a subject I find quite complex. The pinion gear part #'s and design were changing rapidly in the '64 to '66 period, and again after '68 (if you go by new part #).
Pic shows a 4.56 pinion [9-41 teeth] dated 11-65. One on the right is a 3.70 pinion [10-37] dated 5-65. They are both 30 spline, requiring yoke with cast # 986 (shown). The shaft on the right (from diff FA_7_15_65) has a shoulder that allows the smaller crush sleeve (NOS shown). The larger crush sleeve is from a local jobber rebuild kit [Chicago Rawhide DK323; for GM 12 bolt with 8.875" ring gear -- although the Corvette is 10 bolt with a 6.2" bolt center circle; the bearings seem to be the same].
The '63-64 pinions had the shoulder on the shaft, but with a 14 spline (I think) requiring a different yoke, cast "823".
I'm wondering if this is why the GM parts catalogs seem to indicate 2 different crush sleeves for 1966 (ie. there's an overlap in the years, both types called out for 1966 Corvette). 1965 production pinion gears seem to be unique, having the shoulder and the fine spline. Going by the Nov 1965 date on the shaft on the left, it seems that by then (approx. Jan '66 Corvettes ?), the shaft was smooth/tapered and the larger style crush sleeve was installed.
Does this jive with what you diff rebuilders have seen ? And I haven't a clue what the change was in '69+ gears (but I'm curious).
Pic shows a 4.56 pinion [9-41 teeth] dated 11-65. One on the right is a 3.70 pinion [10-37] dated 5-65. They are both 30 spline, requiring yoke with cast # 986 (shown). The shaft on the right (from diff FA_7_15_65) has a shoulder that allows the smaller crush sleeve (NOS shown). The larger crush sleeve is from a local jobber rebuild kit [Chicago Rawhide DK323; for GM 12 bolt with 8.875" ring gear -- although the Corvette is 10 bolt with a 6.2" bolt center circle; the bearings seem to be the same].
The '63-64 pinions had the shoulder on the shaft, but with a 14 spline (I think) requiring a different yoke, cast "823".
I'm wondering if this is why the GM parts catalogs seem to indicate 2 different crush sleeves for 1966 (ie. there's an overlap in the years, both types called out for 1966 Corvette). 1965 production pinion gears seem to be unique, having the shoulder and the fine spline. Going by the Nov 1965 date on the shaft on the left, it seems that by then (approx. Jan '66 Corvettes ?), the shaft was smooth/tapered and the larger style crush sleeve was installed.
Does this jive with what you diff rebuilders have seen ? And I haven't a clue what the change was in '69+ gears (but I'm curious).
Comment