TRUCK RPM CALCULATOR

How to Use:-

This calculator has two modes Speed → Engine RPM or Engine RPM → Speed. Therefore, select one that you want to calculate.
Enter Road Speed, gear ratio, axle ratio and tire diameter.
This RPM tool will automatically perform the calculations.
Check the calculation results and download the desired report in PDF format.

Download Spreadsheet

Calculate engine RPM from road speed, gearing and tire diameter.

Road Speed Enter the truck's road speed.

mph

Engine RPM Enter engine RPM.

RPM

Transmission Gear Ratio Ratio of the gear currently selected.

Axle / Final Drive Ratio Differential or rear axle ratio.

Tire Diameter Use actual rolling diameter when available.

Common Truck Tire Diameter Select a tire size to automatically enter its approximate diameter.

Engine RPM

1,106

RPM

Wheel RPM

RPM

Overall Ratio

2.25

Tire Revs

475

rev/mile

Speed at 1,000 RPM 58.8 mph

Transmission Ratio 0.73 : 1

Axle Ratio 3.08 : 1

Tire Diameter 42.5 in