Perhaps EdPruss or other Big Bolt GMC owners know if the '53 vacuum operated 2 speed differential is the same as for the Chevy's of the same year group???

GMC Parts book info is often much harder to find, but the Chevy info for that type/year rear axle is readily found which may help in identifying replacement parts???

How about it folks, any correlation between GMC and Chevy rear axles/differentials???

Dan

~ Dan
1951 Chevy 3 window 3100
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"My Grandpa Carl's Truck and How it Became Mine"
1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver)
US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)