Pinion bearings in the 81, K10 went out. Geared 4;10, 4 speed 465, with a 205(?) TC. It has the 10 bolt diff. I have 3 12 bolt truck diffs, 1 in a 78 K10, 1 in a 78 Blazer, both auto trans and 203s I believe. 3rd is in a 80 K 10 465/205.
Figure the 12 bolt in the blazer is the best, and vehicle...