Speedometer Gear Calculator

This calculator helps you determine the correct speedometer driven gear teeth needed when modifying your vehicle's tire size or axle ratio. Here's how to use it:

1. Enter Drive Teeth: Input the number of teeth on your speedometer's drive gear (typically found on the transmission).
2. Input Axle Ratio: Enter your vehicle's axle ratio (e.g., 3.73:1 would be entered as 3.73).
3. Specify Tire Diameter: Enter your new tire's diameter in inches.

Why Recalibrate Your Speedometer?

Speedometer recalibration is crucial when you:

• Install larger or smaller tires
• Change your vehicle's axle ratio
• Notice significant speedometer inaccuracy