35x13.50R20 vs 325/60R20
325/60R20 is a safe swap for 35x13.50R20 by the usual ±3% rule: the diameter differs by +1.01%.
Side by side
| 35x13.50R20 | 325/60R20 | Difference | |
|---|---|---|---|
| Overall diameter | 35.00" | 35.35" | +0.35" (+1.01%) |
| Section width | 343 mm | 325 mm | -18 mm |
| Sidewall | 7.50" | 7.68" | +0.18" |
| Rim | 20" | 20" | same |
| Circumference | 110.0" | 111.1" | +1.1" |
| Revs per mile | 576 | 570 | -6 |
| Ride height | — | — | +0.18" |
| Speedometer reads 60 mph | 60.0 | 60.6 | +0.6 mph |
Speedometer and odometer
With 325/60R20 on a car calibrated for 35x13.50R20, the speedometer reads 59.4 mph when you're really doing 60, and the odometer under-counts by 1.0%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 30.3 mph |
| 45 mph | 45.5 mph |
| 60 mph | 60.6 mph |
| 70 mph | 70.7 mph |
| 80 mph | 80.8 mph |
Other sizes close to 35x13.50R20
Questions
Can I replace 35x13.50R20 with 325/60R20?
325/60R20 is a safe swap for 35x13.50R20 by the usual ±3% rule: the diameter differs by +1.01%.
What's the difference between 35x13.50R20 and 325/60R20?
325/60R20 is 0.35" taller and 18 mm narrower; the sidewall is +0.18". At an indicated 60 mph you'd actually be doing 60.6 mph.
Will 325/60R20 fit on 35x13.50R20 wheels?
Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 325 mm tire and the fender clearance.