35x12.50R17 vs 37x12.50R17 tire size
A 37x12.50R17 is 2.00 inches (51 mm) taller than a 35x12.50R17, and the same width. Fit them in place of 35x12.50R17 tires and the speedometer reads low: at 60 mph on it you’re doing 63.4 mph, 5.7% faster, and the vehicle sits 1.00 inches (25 mm) higher.
Sources checked
| Dimension | 35x12.50R17 | 37x12.50R17 | Change |
|---|---|---|---|
| Overall diameter | 35.00 in (889 mm) | 37.00 in (940 mm) | +2.00 in (+51 mm) |
| Section width | 12.50 in (318 mm) | 12.50 in (318 mm) | 0.00 in (0 mm) |
| Sidewall height | 9.00 in (229 mm) | 10.00 in (254 mm) | +1.00 in (+25 mm) |
| Aspect ratio | 72% | 80% | |
| Rim diameter | 17 in | 17 in | |
| Circumference | 110.0 in (2,793 mm) | 116.2 in (2,952 mm) | +6.2 in |
| Revolutions per mile | 576 | 545 | −31 |
| Revolutions per km | 358 | 339 | −19 |
Check another speed or size
Metric, LT and flotation
At 60 mph on the speedometer you’re doing
63.4mph
+5.7% · the speedometer reads low
- Height
- +2.00 in (+51 mm)
- Width
- 0.00 in (0 mm)
- Ground clearance
- +1.00 in (+25 mm)
- Each side, same wheel
- 0.00 in (0 mm)
35x12.50R17LT and 37x12.50R17LT side by side
| Dimension | 35x12.50R17LT | 37x12.50R17LT | Change |
|---|---|---|---|
| Overall diameter | 35.00 in (889 mm) | 37.00 in (940 mm) | +2.00 in (+51 mm) |
| Section width | 12.50 in (318 mm) | 12.50 in (318 mm) | 0.00 in (0 mm) |
| Sidewall height | 9.00 in (229 mm) | 10.00 in (254 mm) | +1.00 in (+25 mm) |
| Aspect ratio | 72% | 80% | |
| Rim diameter | 17 in | 17 in | |
| Circumference | 110.0 in | 116.2 in | +6.2 in |
| Revolutions per mile | 576 | 545 | −31 |
| Revolutions per km | 358 | 339 | −19 |
The working
- 35x12.50R17LT: 35.00 in tall and 12.50 in wide, as the size says.
- Sidewall = (diameter − rim) ÷ 2 = (35 − 17) ÷ 2 = 9.00 in.
- Circumference = π × 35.00 = 110.0 in; revolutions per mile = 63,360 ÷ 110.0 = 576.
- 37x12.50R17LT: 37.00 in tall and 12.50 in wide, as the size says.
- Sidewall = (diameter − rim) ÷ 2 = (37 − 17) ÷ 2 = 10.00 in.
- Circumference = π × 37.00 = 116.2 in; revolutions per mile = 63,360 ÷ 116.2 = 545.
- Speedometer. True speed = what it shows × new diameter ÷ old = 60 × 37.00 ÷ 35.00 = 63.4 mph.
- Ground clearance. Half the change in diameter: (37.00 − 35.00) ÷ 2 = +1.00 in.
Speedometer
A 37x12.50R17 turns 545 times a mile against the 35x12.50R17’s 576. With a speedometer set for 35x12.50R17, true speed is what it shows × 37.00 ÷ 35.00:
| Speedometer shows | True speed | Difference |
|---|---|---|
| 25 mph | 26.4 mph | +1.4 mph |
| 35 mph | 37.0 mph | +2.0 mph |
| 45 mph | 47.6 mph | +2.6 mph |
| 55 mph | 58.1 mph | +3.1 mph |
| 65 mph | 68.7 mph | +3.7 mph |
| 75 mph | 79.3 mph | +4.3 mph |
Clearance
- Ground clearance: +1.00 in (+25 mm), half the change in diameter.
- Top of the tread: +1.00 in (+25 mm), so that much less room under the fender.
- Each side, on the same wheel: no change.
A new wheel with a different width or offset moves the tire again. The sidewall goes from 9.00 to 10.00 inches.
What tire makers publish
Inflated on the maker’s measuring rim; the percentage is against the arithmetic.
| Tire | Size as printed | Diameter | Width | Revs per mile |
|---|---|---|---|---|
| Toyo Open Country A/T III | 35X12.50R17LT | 34.5 in (−1.4%) | 12.5 in | 602 |
| Nitto Trail Grappler M/T | 35x12.50R17LT | 34.84 in (−0.5%) | 13.19 in | – |
| Toyo Open Country A/T III | 37X12.50R17LT | 36.5 in (−1.4%) | 12.5 in | 569 |
| Nitto Trail Grappler M/T | 37x12.50R17LT | 36.85 in (−0.4%) | 13.43 in | – |
Each size on its own
- 35x12.50R17 tire size: 35.0 × 12.5 in
- 37x12.50R17 tire size: 37.0 × 12.5 in
Other comparisons
Questions
Can I fit 37x12.50R17 tires instead of 35x12.50R17?
They fit the same 17-inch wheels. A 37x12.50R17 is 2.00 inches (51 mm) taller than a 35x12.50R17, and the same width, so check three things first: that your wheels are within the 37x12.50R17’s approved rim width range, which tire makers list for each size; that it clears the fenders and suspension at full lock and full travel; and that its load index meets what your door-jamb placard asks for.
How far off is the speedometer with 37x12.50R17 tires?
With a speedometer set for 35x12.50R17, the speedometer reads low: at 60 mph on it you’re doing 63.4 mph, 5.7% faster. The odometer is off the same way: over 1,000 miles driven it shows 945.9.
Does 37x12.50R17 change the ground clearance?
By +1.00 inches (+25 mm), half the change in diameter, at the axles and at the lowest point under them. The width doesn’t change.
Sources
- Bridgestone Americas: Determining tire size: P-metric, Euro-metric, LT-metric, C-type and flotation sizes, and what each number means (checked October 28, 2026)
- Toyo Tires: Extensa A/S II sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Proxes Sport A/S sizes and specifications: inflated overall diameter and width, revolutions per mile (checked October 28, 2026)
- Toyo Tires: Open Country A/T III sizes and specifications: P-metric, LT-metric and flotation sizes, with revolutions per mile (checked October 28, 2026)
- Nitto Tire: Trail Grappler M/T sizes and specs: inflated overall diameter and width, LT-metric and flotation sizes (checked October 28, 2026)
Spotted a number that doesn’t match your manual or a source? Tell us; corrections are logged on the sources page.