TireFitLab

285/45 R22 vs 37x13.50 R20

285/45 R22 vs 37x13.50 R20

37x13.50 R20 is outside the configured tolerance for 285/45 R22: +15.3% diameter and +15.3% speedometer effect.

Fitment verdict

37x13.50 R20 is outside the configured tolerance for 285/45 R22: +15.3% diameter and +15.3% speedometer effect.

Metric This size: 285/45 R22 Alternative: 37x13.50 R20 Difference Verdict
Overall diameter 32.10 in 37.00 in +15.3% Too tall
Section width 11.22 in 13.50 in +2.28 in Computed difference
Sidewall height 5.05 in 8.50 in +3.45 in Computed difference
Circumference 100.84 in 116.24 in +15.3% Too tall
Speedo 0.0% +15.3% +15.3% Outside tolerance

Compare sizes

Looks valid
Looks valid
Units
✕ Out of toleranceDiameter +15.3% (+4.90 in) · US (~3%)
  • Out of tolerance · Diameter +15.3%.
  • Speedo @ 60: 60 mph → 69.2 mph.
  • Sidewall +3.45 in · Width +2.28 in.
Diameter+15.3%+4.90 in
Speedo @ 60+15.3%60 mph → 69.2 mph
Sidewall+3.45 inWidth +2.28 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
32.10 in 37.00 in+4.90 in
Sidewall
5.05 in 8.50 in+3.45 in
Width
11.22 in 13.50 in+2.28 in
Circumference
100.84 in 116.24 in+15.3%
Revs / mile
628 545
Speedo @ 60
60 mph 69.2 mph+15.3%
Δ⌀ +124.5 mm
  • Current — 285/45 R22
  • New — 37x13.50 R20
  • Grounded to the road: the axle rises +2.45 in.

Result report

285/45 R22 37x13.50 R20 · Out of tolerance

Use this size when shopping: 37x13.50 R20

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 235/60R21+0.0%+0.0%
OE 285/45R22+0.0%+0.0%
+1″ 165/70R23-0.0%-0.0%
+2″ 205/50R24-0.1%-0.1%

285/45 R22 · 37x13.50 R20 · Methodology

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