I know my truck was originally a 6 cylinder. I keep reading that there are different U joint sizes for some trucks that had "heavy duty" transmissions. Anyone know which ones I need?

I need to replace my PG rear seal, and thought it might be good to do the U's while the driveshaft was out.


1957 Chevy Panel Truck, powered by SBC 350 from 1977 Camaro
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