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Pyrotechnic · 04-12-2008, 07:48 PM

Highway gears like 2.73's will DESTROY your city mileage, and could possible hurt highway mileage too.

The entire point of an overdrive transmission is to be able to run a numerically high gear like a 3.73 to multiply torque while accelerating and keep the load of the engine, but at the same time be able to shift into overdrive on the highway and keep RPM's down.

With 2.73's and a 3 speed 1:1 transmission, you are basically in overdrive in 3rd gear already. If you add a overdrive, thats just way too much gear reduction. It might be useful at 150 MPH, but your truck would have taken flight before that speed.

Trust me, with 28" to 30" tall tires, 3.73's gears are the sweet spot for a 700R4. If you are getting 13-14 MPG now, you would probably be up to 16-17 with 3.73's.

04-12-2008, 07:48 PM	#5
Pyrotechnic Registered User Join Date: Feb 2007 Location: Austin, TX Posts: 3,930	Re: Carb spacers. pros/cons Highway gears like 2.73's will DESTROY your city mileage, and could possible hurt highway mileage too. The entire point of an overdrive transmission is to be able to run a numerically high gear like a 3.73 to multiply torque while accelerating and keep the load of the engine, but at the same time be able to shift into overdrive on the highway and keep RPM's down. With 2.73's and a 3 speed 1:1 transmission, you are basically in overdrive in 3rd gear already. If you add a overdrive, thats just way too much gear reduction. It might be useful at 150 MPH, but your truck would have taken flight before that speed. Trust me, with 28" to 30" tall tires, 3.73's gears are the sweet spot for a 700R4. If you are getting 13-14 MPG now, you would probably be up to 16-17 with 3.73's.