| Recommended Towing RPM | |
| 4 cyl | 2200-3200 |
| 6 cyl | 2000-3000 |
| Big Block | 1600-2600 |
| Small Block | 1800-2800 |
| Ford 6.0L | 1900-2400 |
| Ford Diesel (Non-Turbo) | 1600-2500 |
| Ford Diesel (Turbo) | 1400-2200 |
| Dodge Diesel | 1400-2200 |
| GM Diesel 6.2L | 1800-2800 |
| GM Duramax Diesel | 1800-2400 |
Street tires are rated using three numbers for example 225/70R15 or 255/70/15. In our example 225 is the Width in mm if the tire was measured from the bottom of bead to bottom of bead. In our example 70 is the Aspect, which means that the sidewall is 70% as tall as the tread is wide. In our example 15 is the the Wheel, the size of the wheel in inches, also called rim size. Placing the example numbers in the corresponding fields you will get a Tire Height of 27.4. Place your corresponding numbers into the fields below to calculate your tire height.