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MylilBowTie · 12-19-2006, 03:31 AM

4L80E has these gear ratios. 1st: 2.48 2nd: 1.48 3rd: 1.0 Overdrive: 0.75
Its going to be pretty expensive to get the 4L80E they run about 1200-1500 and you will need a transmission controller. I think they still run about the same price as the transmission or right at it. I think the driveshaft may need to be shortend also.

The overdrive would be better but cost is alot more. With the overdrive you would want to keep your gears. The tall tires and the weight of the truck will need help to get moving. Then you have overdrive for the highway and it wont lug the engine locking and unlock the convertor all the time.

3.42 gears will lower the rpm some. The gears don't cost much but the labor does to get them installed. Have you thought about different tire sizes? I take it you have a th350 or th400?

12-19-2006, 03:31 AM	#3
MylilBowTie Right turn Clyde Join Date: Nov 2002 Location: Cincinnati, Ohio Posts: 2,911	Re: Overdrive or Gears 4L80E has these gear ratios. 1st: 2.48 2nd: 1.48 3rd: 1.0 Overdrive: 0.75 Its going to be pretty expensive to get the 4L80E they run about 1200-1500 and you will need a transmission controller. I think they still run about the same price as the transmission or right at it. I think the driveshaft may need to be shortend also. The overdrive would be better but cost is alot more. With the overdrive you would want to keep your gears. The tall tires and the weight of the truck will need help to get moving. Then you have overdrive for the highway and it wont lug the engine locking and unlock the convertor all the time. 3.42 gears will lower the rpm some. The gears don't cost much but the labor does to get them installed. Have you thought about different tire sizes? I take it you have a th350 or th400? __________________ 1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI