I agree with Fred T and Tony. I went to Advance Auto, and I'm sure they listed the same u-joints for the front and rear. Have you checked to see if your tires are balanced? John.

1968 Chevy C-10, 250 and 3 speed on floor, Hedman headers, Offy intake, Edelbrock 600cfm 4 barrel, HEI
1966 Chevy C-10, motor and tranny went into the '68. Waiting to be restored.