225/45R17 vs 235/60R17
New overall diameter
28.10″
was 24.97″
True speed at an indicated 60
67.5 mph
your speedo reads low
Revolutions per mile
718
was 808, −90
| Measurement | 225/45R17 | 235/60R17 | Change |
|---|---|---|---|
| Overall diameter | 24.97″ | 28.10″ | +3.13″ (+12.5%) |
| Sidewall height | 3.99″ (101.3 mm) | 5.55″ (141.0 mm) | +39.8 mm |
| Tread width | 225 mm | 235 mm | +10 mm |
| Circumference | 78.45″ | 88.29″ | +9.83″ |
| Revs per mile | 808 | 718 | −90 |
| Speedometer error | baseline | +12.5% | reads low |
Diameter overlay
225/45R17 235/60R17
Speedometer check
With 235/60R17 fitted, when the speedometer shows the indicated speed, your actual speed is:
25 mph shown
28.1 mph actual
35 mph shown
39.4 mph actual
45 mph shown
50.6 mph actual
55 mph shown
61.9 mph actual
65 mph shown
73.1 mph actual
75 mph shown
84.4 mph actual
Common questions
- Will 235/60R17 fit instead of 225/45R17?
- Overall diameter changes 12.5%; section width changes 10 mm. Diameter comparison alone cannot confirm fitment. Verify the vehicle maker's approved rim width, tire load and speed ratings, and clearance at full steering lock and suspension compression. Confirm any possible ABS, traction-control, speedometer, and drivetrain effects with the vehicle maker or a qualified tire professional. Overall diameter goes from 24.97″ to 28.10″, a change of +12.5%. The rule of thumb most shops use: under 3% is fine, 3 to 5% needs a clearance check, over 5% needs recalibration.
- How far off will my speedometer read on 235/60R17?
- At an indicated 60 mph you are really doing about 67.5 mph, a +12.5% error. The speedometer reads low, so you are going faster than it shows.
- What is the difference in revolutions per mile between 225/45R17 and 235/60R17?
- 225/45R17 turns about 808 times per mile and 235/60R17 turns about 718, a difference of −90. Your speedometer and odometer both count rotations, so this number is what throws them off.