Help me out on this one - from my 1946 half-ton gear swap issue:

I installed a new 3:55 gear set and after all is completed I drove it down my driveway and heard a noise when backing off the accelerator. Opened the differential cover to see the marks in the carrier from the pinion gear. What did I miss? What keeps the pinion gear and shaft from moving forward and backward???

Help me out on this one. 46 half ton gear swap issue
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Last edited by Peggy M; 07/23/2024 4:34 PM. Reason: added more info to the title
1946 Chevy 1/2 ton "patina" pickup with a 1953 235 engine, otherwise all stock and unmolested!