| Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I think with the advent of tubeless tires and appropriate wheels, GM went to the larger ID wheels to keep old tube type wheels off 'modern' axles. Adam's '54' might have been an early application.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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