i'm not sure but i think it's the same as chevy.what i have is a open drive shaft with at least 6 to 1 ratio with 2 speed axel with original 20" rims.motor has been changed to 5.9 cummins with 5 speed trans.i'm going to use it to pull my 42 1/2 ton .65 is plenty fast .kinda looking change it out to 3.54.


1940 GMC AC 302 1 1/2-Ton Dually
BOHEMIATH
In the Stovebolt Gallery
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