185/60R15 vs 175/65R15
175/65R15 is a safe swap for 185/60R15 by the usual ±3% rule: the diameter differs by +0.91%.
Speedometer and odometer
With 175/65R15 on a car calibrated for 185/60R15, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.9%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.3 mph |
| 45 mph | 45.4 mph |
| 60 mph | 60.5 mph |
| 70 mph | 70.6 mph |
| 80 mph | 80.7 mph |
Other sizes close to 185/60R15
- 185/60R15 vs 185/65R15+3.07%
- 185/60R15 vs 195/60R15+1.99%
- 185/60R15 vs 205/50R15-2.82%
- 185/60R15 vs 195/50R16-0.27%
- 185/60R15 vs 195/55R15-1.24%
- 185/60R15 vs 185/55R15-3.07%
- 185/60R15 vs 205/60R15+3.98%
- 185/60R15 vs 175/70R14-0.40%
- 185/60R15 vs 225/45R15-3.23%
- 185/60R15 vs 195/50R15-4.48%
- 185/60R15 vs 225/50R15+0.50%
- 185/60R15 vs 245/40R15-4.31%
Questions
Can I replace 185/60R15 with 175/65R15?
175/65R15 is a safe swap for 185/60R15 by the usual ±3% rule: the diameter differs by +0.91%.
What's the difference between 185/60R15 and 175/65R15?
175/65R15 is 0.22" taller and 10 mm narrower; the sidewall is +0.11". At an indicated 60 mph you'd actually be doing 60.5 mph.
Will 175/65R15 fit on 185/60R15 wheels?
Both use a 15" rim, so the wheel diameter matches; check the wheel's width range for a 175 mm tire and the fender clearance.