A friend of mine pulled the old bearing off of my old pinion to see what size shim I would need on my new pinion. I am keeping the same 4.10 gear ratio. We thought that there was only one shim b/n the bearing and the back of the pinion. There were two shimes that he measured at .035 each. He wanted to know if there should be two and what the total thickness should be. The old gears had gear whine on the coast side, so I don't know if we should add more shims or take some away. We haven't installed the gears yet, so we haven't seen the gear marks on the ring gear. I would appreciate anyones .02 worth.