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monzaz · 04-21-2010, 01:16 AM

Ok the drop out is a 1964 date code on the ring gear
AXLE spline is coarse
ring and pinion ratio trying to remember (8 on the pinion 36 on the ring ) 4.50 ratio??? maybe a few teeth off

Anyway it have a 10" ring gear + or - a 1/4" ish

has a bolt in pinion from the front like FORD 9" (5 bolts)

Ring gear bolts are on the inner diameter of the ring gear NOT in the traditional late model back side of the ring gear behind the ring gear teeth (IE 12 bolt chevy 10, bolt 8.5 etc. )

Does have the fifth bearing like a Ford 9" also BUT bigger.

Does this sound like a c30 c40 c50 c60 truck rear?

I have casting numbers i can get too if that helps. Jim

Thanks everyone

04-21-2010, 01:16 AM	#1
monzaz Registered User Join Date: Jan 2010 Location: Richfield, Oh Posts: 5	GMC GM drop out thrid member REAR END ID question Ok the drop out is a 1964 date code on the ring gear AXLE spline is coarse ring and pinion ratio trying to remember (8 on the pinion 36 on the ring ) 4.50 ratio??? maybe a few teeth off Anyway it have a 10" ring gear + or - a 1/4" ish has a bolt in pinion from the front like FORD 9" (5 bolts) Ring gear bolts are on the inner diameter of the ring gear NOT in the traditional late model back side of the ring gear behind the ring gear teeth (IE 12 bolt chevy 10, bolt 8.5 etc. ) Does have the fifth bearing like a Ford 9" also BUT bigger. Does this sound like a c30 c40 c50 c60 truck rear? I have casting numbers i can get too if that helps. Jim Thanks everyone