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**swervin ervin** · 02-06-2007, 06:21 PM

Yeah, my 85 came stock with 2.73 gears and a 700-R4 tranny. 86k10 is correct, the gears are way too high for an overdrive tranny. I have 3.73 gears in mine now and I'm way happier.

As for why GM does stuff, who knows. They sure don't have any logical reason I can think of. It was a gas mileage reason I'm guessing but what they didn't take into consideration is overdrive. With the high gears it would always unlock and drop down into a lower gear, especially going up hills. A lower rear gear would keep it locked into overdrive and thus save on gas in the long run.

02-06-2007, 06:21 PM	#22
swervin ervin You get what you pay for Join Date: Dec 1999 Location: Cherryville, NC Posts: 4,798	Re: Rear End Id, Tranny Id? Yeah, my 85 came stock with 2.73 gears and a 700-R4 tranny. 86k10 is correct, the gears are way too high for an overdrive tranny. I have 3.73 gears in mine now and I'm way happier. As for why GM does stuff, who knows. They sure don't have any logical reason I can think of. It was a gas mileage reason I'm guessing but what they didn't take into consideration is overdrive. With the high gears it would always unlock and drop down into a lower gear, especially going up hills. A lower rear gear would keep it locked into overdrive and thus save on gas in the long run.