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68longhorn · 08-19-2010, 10:12 AM

An overdrive trans will most likely only help on the highway, If you go with a 700R4 the steep 1st gear may help mileage in the city slightly because the engine will work less to get her moving. (Thats theory based, I have no proof of this occuring). Another thing you could try would be locking up your converter in 2nd or 3rd gear, It makes a solid link from the motor to trans so you don't get slippage. It is used in drag racing and increasesthe mph of a run, but never seen it done like that on the street. The hang on units like gear vendors seem neat, and I know people who say they work great. Not 100% sure,but I believe you can overdrive each gear, so your 350 could go 1st, 1st-OD, 2nd, 2nd-OD, 3rd, 3rd-OD. That could help in the city.

I'm not familiar with the rear options for your truck, but I've been told steeper gears help fuel economy in stop and go because it doesn't work the motor as hard on starts. Hopefully someone with a little more experience can chime in with what they have done.

08-19-2010, 10:12 AM	#5
68longhorn Registered User Join Date: Jun 2007 Location: Cape Coral, Florida Posts: 1,123	Re: Higher gear for differential An overdrive trans will most likely only help on the highway, If you go with a 700R4 the steep 1st gear may help mileage in the city slightly because the engine will work less to get her moving. (Thats theory based, I have no proof of this occuring). Another thing you could try would be locking up your converter in 2nd or 3rd gear, It makes a solid link from the motor to trans so you don't get slippage. It is used in drag racing and increasesthe mph of a run, but never seen it done like that on the street. The hang on units like gear vendors seem neat, and I know people who say they work great. Not 100% sure,but I believe you can overdrive each gear, so your 350 could go 1st, 1st-OD, 2nd, 2nd-OD, 3rd, 3rd-OD. That could help in the city. I'm not familiar with the rear options for your truck, but I've been told steeper gears help fuel economy in stop and go because it doesn't work the motor as hard on starts. Hopefully someone with a little more experience can chime in with what they have done.