Use this calculator to determine your gear ratio and vehicle’s speed in any gear and any engine RPM for best performance.
Scroll through the list of popular transmissions to find yours. Or, change input variables (engine RPM, axle gear ratio and tire height) to determine vehicle speed in each forward gear.
For the Tire Height field, enter your tire diameter in inches. For more information, read “What’s on your tire’s sidewall,”
As an added bonus, the Gear Ratio Calculator doubles as a Vehicle Speed Calculator.
TREMEC ASPECT RATIO CALCULATOR: Find your tire height using this calculator.