TireFitLab

235/70 R17 vs 31x10.50 R15

235/70 R17 vs 31x10.50 R15

31x10.50 R15 is outside the configured tolerance for 235/70 R17: +3.5% diameter and +3.5% speedometer effect.

Fitment verdict

31x10.50 R15 is outside the configured tolerance for 235/70 R17: +3.5% diameter and +3.5% speedometer effect.

Metric This size: 235/70 R17 Alternative: 31x10.50 R15 Difference Verdict
Overall diameter 29.95 in 31.00 in +3.5% Too tall
Section width 9.25 in 10.50 in +1.25 in Computed difference
Sidewall height 6.48 in 8.00 in +1.52 in Computed difference
Circumference 94.10 in 97.39 in +3.5% Too tall
Speedo 0.0% +3.5% +3.5% Outside tolerance

Compare sizes

Looks valid
Looks valid
Units
✕ Out of toleranceDiameter +3.5% (+1.05 in) · US (~3%)
  • Out of tolerance · Diameter +3.5%.
  • Speedo @ 60: 60 mph → 62.1 mph.
  • Sidewall +1.52 in · Width +1.25 in.
Diameter+3.5%+1.05 in
Speedo @ 60+3.5%60 mph → 62.1 mph
Sidewall+1.52 inWidth +1.25 in
How this result is calculated

Computed from nominal tire-size geometry: diameter, circumference and speedometer error. It does not check wheel-arch, suspension or brake clearance.

Methodology
Diameter
29.95 in 31.00 in+1.05 in
Sidewall
6.48 in 8.00 in+1.52 in
Width
9.25 in 10.50 in+1.25 in
Circumference
94.10 in 97.39 in+3.5%
Revs / mile
673 651
Speedo @ 60
60 mph 62.1 mph+3.5%
Δ⌀ +26.6 mm
  • Current — 235/70 R17
  • New — 31x10.50 R15
  • Grounded to the road: the axle rises +0.52 in.

Result report

235/70 R17 31x10.50 R15 · Out of tolerance

Use this size when shopping: 31x10.50 R15

Use this size when shopping

Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 295/60R16-0.1%-0.1%
OE 235/70R17+0.0%+0.0%
+1″ 275/55R18-0.1%-0.1%
+2″ 185/75R19-0.1%-0.1%

235/70 R17 · 31x10.50 R15 · Methodology

Last reviewed: 2026-06-28
What changed
  • Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.