Casting on the diff is 3707340 or 3707343. Located on pass side.
The other code is a circle(like a zero with something in the center) and D1
This is in a 1955 series 2 3100.

Question 2: Why is there nothing mentioned about rear differentials in the 1955 factory assembly manual?

Thanks in advance
Jim


Jim

1955 Chevy series 2
6 cylinder, 3 on the tree
Short bed, step side