BACK   RPM Calculator Enter ratio, tire height and mph and click solve to calculate RPM. ratio tire height mph Auto* AOD Manual* 5 Speed Recommended RPM @ 60 mph: 4 cyl: 2200-3200 6 cyl: 2000-3000 Sm. Block: 1800-2800 Big Block: 1600-2600 GM Diesel 6.2L: 1800-2800 Ford Diesel - Non-turbo: 1600-2500 Ford Diesel - Turbo 1400-2200 Dodge Diesel: 1400-2200 *Auto = D in an AOD *Manual = 4th in a 5 speed     For Specific Transmission Ratio R&P Ratio Tire Height MPH Trans Ratio