Something just not right here, you have gone from low 30s to 41 to 38 without really any pattern change on the drive side. Did you change the large pinion bearing race.........is there anything under it, another shim, dirt, metal shaving. Your pattern should have moved. Are you shimming under the bearing or the race. If under the bearing is it bearing that has been honed to slide on and off........is it going all the way down to the shim?????? Something here isn't chaging like it should
New Koyo bearings & races. Everything is clean and seated properly. Double checked everything. There were changes that i could see with the naked eye like depth of the gear swipe. The pattern on the coast side move from toe to heel & visa versa. The drive side pattern now swipes to a point from toe to heel 2/3 of the gear face. Like someone else mentioned earlier, maybe these gears weren't setup correctly to begin with in the vehicle they came out of. I think they are well used gears and I won't buy used ever again. What's the best brand of new gears to buy?
People buy used gears ...1 for the price and 2 usually they are the quietest compared to all after market gears because of the way the gear faces are machined. They are for A - B street cars and trucks. for longevity in regular driving and quietness. Aftermarket gears are more for the street pounders and strength factor of higher torque and HP drive lines. As long as you go with a brand name gear you should be fine Motive, Yukon, US gear...I like Nitro gear they have been great for us on set-up noise and strength. I have not had issues with excel, richmond, etc. BUT remember anygear can make noise and or fail if not set-up or broken in correctly. Good luck, Jim J D
Favor... Open the backlash up another .004 and see what .014 backlash swipes at. That would tell us if the pinion nut was loose and they ran it that way for a while. The .038 sure looks to be what the coast side will probably be. how does it sound when spinning the ring and pinion forward and reverse?