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old yelr · 01-22-2012, 01:44 PM

The label in the glovebox should tell you the gear ratio, but if it's missing all you have to do is count the teeth on the ring and pinion gears and then devide the smaller number by the bigger number and that's your ratio. It's probably 4:10 or 3:73 and it looks like a G80 rear end which is factory limited slip.

01-22-2012, 01:44 PM	#19
old yelr Registered User Join Date: Nov 2011 Location: Winnipeg, Manitoba Posts: 164	Re: 1978 GMC Sierra C35 "Project Second Life" The label in the glovebox should tell you the gear ratio, but if it's missing all you have to do is count the teeth on the ring and pinion gears and then devide the smaller number by the bigger number and that's your ratio. It's probably 4:10 or 3:73 and it looks like a G80 rear end which is factory limited slip.