Tire size comparison
285/70R17 vs 35x11.50R17
35x11.50R17 is +7.0% taller than 285/70R17: 35.0 in vs 32.7 in (+2.29 in), and 0.3 in wider. With 35x11.50R17 on a vehicle set up for 285/70R17, the speedometer shows 60 mph at an actual 64.2 mph. That is more than the ±3% difference many shops use as a rule of thumb, so check carefully before switching.
Set up for: going bigger (35x11.50R17 instead of 285/70R17) · Different situation?
Your current size
e.g. 265/70R17, 2657017 or 33x12.50R20
Where do I find my size?
It's on the tire sidewall, e.g. P265/70R17 115T, and on the tire placard sticker on the driver's door jamb (also in the owner's manual). The placard shows the size the vehicle came with; the sidewall shows what is fitted now. If they differ, use the placard as your starting point. Digits are enough here: 2657017 or 33125020.
Size you're considering
285/70R17 vs 35x11.50R17: full comparison
| 285/70R17 | 35x11.50R17 | Difference | |
|---|---|---|---|
| Overall diameter | 32.71 in | 35.00 in | +2.29 in (+7.0%) |
| Width | 11.22 in | 11.50 in | +0.28 in (+2.5%) |
| Sidewall height | 7.85 in | 9.00 in | +1.15 in |
| Circumference | 102.8 in | 110.0 in | +7.2 in |
| Revs per mile (nominal) | 617 | 576 | −40 |
| Wheel diameter | 17 in | 17 in | ±0 in |
| Diameter in mm | 831 | 889 | +58 mm |
Speedometer difference
Your speedometer is calibrated for 285/70R17. Fitted with 35x11.50R17, the actual speed is the reading × 35.00 ÷ 32.71.
| Speedometer shows | Actual speed | Difference |
|---|---|---|
| 20 mph | 21.4 mph | +1.4 mph |
| 30 mph | 32.1 mph | +2.1 mph |
| 45 mph | 48.2 mph | +3.2 mph |
| 55 mph | 58.9 mph | +3.9 mph |
| 60 mph | 64.2 mph | +4.2 mph |
| 70 mph | 74.9 mph | +4.9 mph |
| 80 mph | 85.6 mph | +5.6 mph |
Real tires: published diameters
285/70R17: 32.7–33.15 in published by 6 makers; 35x11.50R17: 34.5–35 in published by 3 makers. Calculated figures assume a nominal tire; the exact difference between two specific tires depends on their models.
More about each size: 285/70R17 · 35x11.50R17
Related comparisons
FAQ
Which is bigger, 285/70R17 or 35x11.50R17?
35x11.50R17 is +7.0% taller than 285/70R17: 35.0 in vs 32.7 in (+2.29 in).
How much will my speedometer be off with 35x11.50R17 instead of 285/70R17?
The speedometer is calibrated for 285/70R17. With 35x11.50R17 it shows 60 mph when you are doing 64.2 mph, and 70 mph at 74.9 mph (+7.0%). Your speedometer also has its own factory tolerance.
Can I replace 285/70R17 with 35x11.50R17?
The diameter difference is +7.0%. Whether it fits depends on things this calculation can't see: wheel width and offset, clearance at full lock and over bumps, load index and speed rating, and your vehicle maker's approval. Check your door-jamb placard and owner's manual and ask a tire professional.