Dave's Off-Road Gear Ratio and Tire Size RPM Calculator

How fast will my engine have to run?

A sketch of my truck by Dave Gauer

This calculator is aimed at offroad vehicles with rear wheel and four wheel/all wheel drive. You could conceivably use it for any vehicle as long as your transmission is listed and you know your differential gear ratio. I'd be more than happy to add a specific transmission. Contact me with the specs.

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