31x10.50R15 vs 275/70R16
275/70R16 is a safe swap for 31x10.50R15 by the usual ±3% rule: the diameter differs by +0.51%.
Side by side
| 31x10.50R15 | 275/70R16 | Difference | |
|---|---|---|---|
| Overall diameter | 31.00" | 31.16" | +0.16" (+0.51%) |
| Section width | 267 mm | 275 mm | +8 mm |
| Sidewall | 8.00" | 7.58" | -0.42" |
| Rim | 15" | 16" | +1" |
| Circumference | 97.4" | 97.9" | +0.5" |
| Revs per mile | 651 | 647 | -3 |
| Ride height | — | — | +0.08" |
| Speedometer reads 60 mph | 60.0 | 60.3 | +0.3 mph |
Speedometer and odometer
With 275/70R16 on a car calibrated for 31x10.50R15, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.5%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.2 mph |
| 45 mph | 45.2 mph |
| 60 mph | 60.3 mph |
| 70 mph | 70.4 mph |
| 80 mph | 80.4 mph |
Other sizes close to 31x10.50R15
Questions
Can I replace 31x10.50R15 with 275/70R16?
275/70R16 is a safe swap for 31x10.50R15 by the usual ±3% rule: the diameter differs by +0.51%.
What's the difference between 31x10.50R15 and 275/70R16?
275/70R16 is 0.16" taller and 8 mm wider; the sidewall is -0.42". At an indicated 60 mph you'd actually be doing 60.3 mph.
Will 275/70R16 fit on 31x10.50R15 wheels?
No — 31x10.50R15 needs a 15" wheel and 275/70R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.