235/40R19 vs 245/40R19Tire Size Comparison

Safe

The 1.2% diameter difference is within the accepted 3% tolerance.

235/40R19671mm dia245/40R19679mm dia+4.0mm

Comparison Details

Overall Diameter670.6 vs 678.6 mm (+8.0 mm)
Diameter Difference+1.19%
Section Width235 vs 245 mm (+10 mm)
Sidewall Height94.0 vs 98.0 mm (+4.0 mm)
Circumference2106.8 vs 2131.9 mm
Clearance Change+4.0 mm
Speedometer Error+1.19%
Revs/Mile764 vs 755

Speedometer Correction

When switching from 235/40R19 to 245/40R19, your speedometer will differ from actual speed.

SpeedometerActual SpeedDifference
30 km/h30.4 km/h+0.4 km/h
40 km/h40.5 km/h+0.5 km/h
50 km/h50.6 km/h+0.6 km/h
60 km/h60.7 km/h+0.7 km/h
70 km/h70.8 km/h+0.8 km/h
80 km/h81.0 km/h+1.0 km/h
90 km/h91.1 km/h+1.1 km/h
100 km/h101.2 km/h+1.2 km/h
110 km/h111.3 km/h+1.3 km/h
120 km/h121.4 km/h+1.4 km/h
130 km/h131.6 km/h+1.6 km/h

Vehicles Using These Sizes

Vehicles with 235/40R19

Vehicles with 245/40R19

Individual Tire Size Details

Practical Guidance

Switching from 235/40R19 to 245/40R19 is within the industry-accepted 3% diameter tolerance. Your speedometer, ABS, and traction control should function normally. Both sizes fit the same 19-inch rim, so no wheel change is needed.

The 3% diameter tolerance is a widely accepted industry guideline referenced by the ETRTO and most vehicle manufacturers. When in doubt, consult your vehicle's owner's manual or a qualified tire professional. For U.S. tire safety standards and recalls, see the NHTSA Tire Safety page.

Frequently Asked Questions

Safe. The overall diameter differs by 1.19%, width changes by 10mm.

Speedometer error will be 1.19%. At an indicated 100 km/h, actual speed is about 101.2 km/h.

Ground clearance changes by +4.0mm per side.