Advertisement
Visit Our Friendly Website

Gear Ratio and Tire Size Chart

This gear ratio and tire diameter chart meant to give you an approximation of ideal RPMs at highway speed (65 mph) for three situations: fuel economy, everyday driving, and increased towing power.

This chart provides values that represent a 1:1 ratio on a manual transmission. 

Gear ratio and tire diameter charts are ideal for making your car as efficient as possible.

Note: Automatic transmission RPMs tend to be a little higher and transmissions with an overdrive tend to be lower.

Here’s a formula you can use to calculate your vehicle’s tire diameter:

(CROSS SECTION WIDTH x 0.ASPECT RATIO x 2 ÷ 25.4) + WHEEL DIAMETER = OVERALL TIRE DIAMETER

For Example:

235/45ZR-17

(235 x 0.45 x 2 ÷ 25.4) + 17 = 25.327″

And here’s a formula that you can use to calculate your vehicle’s rear axle gear ratio:

RING GEAR TOOTH COUNT ÷ PINION GEAR TOOTH COUNT = GEAR RATIO

For example:

41-tooth ring gear ÷ 10-tooth pinion gear = 4.10

See More:

Ekster EU

2 Comments

Add a Comment

Your email address will not be published.

Advertisement