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Old 07-19-2008, 07:41 PM   #9 (permalink)
Big Dave
Master EcoModder
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Join Date: Jan 2008
Location: Steppes of Central Indiana
Posts: 1,313

The Red Baron - '00 Ford F-350 XLT
90 day: 27.99 mpg (US)

Impala Phase Zero - '96 Chevrolet Impala SS
90 day: 21.03 mpg (US)
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Having done the gear swap thing (3.73 to 3.08) I can tell you it is effective. I gained 3 MPG from doing it. But I have a diesel known for its huge low-end torque.

Before you do a gear swap, I'd recommend a long talk with an automatic transmission expert. A numerically lower rear end will slow down your torque converter and reduce ATF flow through the cooler, attenuating cooling. In a pickup, this leads to spectacular transmission failures - parts and fluid scattered down the road. Been there, done that.
2000 Ford F-350 SC 4x2 6 Speed Manual
4" Slam
3.08:1 gears and Gear Vendor Overdrive
Rubber Conveyor Belt Air Dam
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