38x13.50R20 vs 38x15.50R20
38x15.50R20 is a safe swap for 38x13.50R20 by the usual ±3% rule: the diameter differs by 0.00%.
Side by side
| 38x13.50R20 | 38x15.50R20 | Difference | |
|---|---|---|---|
| Overall diameter | 38.00" | 38.00" | 0.00" (0.00%) |
| Section width | 343 mm | 394 mm | +51 mm |
| Sidewall | 9.00" | 9.00" | 0.00" |
| Rim | 20" | 20" | same |
| Circumference | 119.4" | 119.4" | 0.0" |
| Revs per mile | 531 | 531 | 0 |
| Ride height | — | — | 0.00" |
| Speedometer reads 60 mph | 60.0 | 60.0 | 0.0 mph |
Speedometer and odometer
With 38x15.50R20 on a car calibrated for 38x13.50R20, the speedometer reads 60.0 mph when you're really doing 60, and the odometer over-counts by 0.0%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.0 mph |
| 45 mph | 45.0 mph |
| 60 mph | 60.0 mph |
| 70 mph | 70.0 mph |
| 80 mph | 80.0 mph |
Other sizes close to 38x13.50R20
Questions
Can I replace 38x13.50R20 with 38x15.50R20?
38x15.50R20 is a safe swap for 38x13.50R20 by the usual ±3% rule: the diameter differs by 0.00%.
What's the difference between 38x13.50R20 and 38x15.50R20?
38x15.50R20 is 0.00" taller and 51 mm wider; the sidewall is 0.00". At an indicated 60 mph you'd actually be doing 60.0 mph.
Will 38x15.50R20 fit on 38x13.50R20 wheels?
Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 394 mm tire and the fender clearance.