I just went through this with rebuilding of my muncie 3 sp. in my 53. Seems GM was making some progress with their auto and light pickup transmissions. Up to and including 52 the transmissions had a single row of needle bearings in the clutch gear. These transmissions were known to pop out of high gear easy when they could/would get some miles on them. In 53 the first design included a double row of needle bearings in the clutch gear, 24 of little ones and 14 of the bigger needle bearings on the inboard side of the clutch gear. The second design increased the diameter of the clutch gear ,but still retained the two rows of needle bearings. Also believe there was a main shaft change to accommodate the second row of needle bearings, but not sure.

Last edited by sstock; 05/12/2018 3:10 PM.

1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration