225/55R18 vs 235/55R19 Side-by-side tire size comparison with specs and compatibility

225/55R18⌀ 705mm235/55R19⌀ 741mm+18.2mm
Compatibility
+5.17% diameter difference
✗ Not Recommended

This tire swap exceeds 5% diameter difference. Not recommended without suspension modifications. Will significantly affect speedometer, ABS, and may cause rubbing.

Full Specifications Comparison

Specification 225/55R18 235/55R19 Difference
Overall Diameter 704.7 mm (27.7") 741.1 mm (29.2") +36.4 mm
Section Width 225 mm (8.9") 235 mm (9.3") +10 mm
Sidewall Height 123.8 mm 129.3 mm +5.5 mm
Circumference 2213.9 mm 2328.2 mm +114.3 mm
Revolutions/Mile 727 691 -36
Aspect Ratio 55% 55% 0%
Rim Diameter 18" 19" +1"

Key Impact Summary

Ground Clearance
+18.2 mm
Speedometer Error
+5.17%
Width Change
+10 mm
Sidewall Change
+5.5 mm

Speedometer Correction Table

When switching from 225/55R18 to 235/55R19, your speedometer will under-read. Here is the correction at common speeds:

Speedometer Shows Actual Speed (mph) Difference
30 mph 31.5 mph +1.5 mph
40 mph 42.1 mph +2.1 mph
50 mph 52.6 mph +2.6 mph
60 mph 63.1 mph +3.1 mph
70 mph 73.6 mph +3.6 mph
80 mph 84.1 mph +4.1 mph
90 mph 94.6 mph +4.6 mph
100 mph 105.2 mph +5.2 mph
110 mph 115.7 mph +5.7 mph
120 mph 126.2 mph +6.2 mph

What This Swap Means

Wider tires (235/55R19): The 10mm wider contact patch provides better grip in dry conditions and improved cornering stability. However, wider tires increase rolling resistance slightly, which may affect fuel economy by 1-2%. They are also more susceptible to hydroplaning in wet conditions.

Taller sidewall: The 5.5mm increase in sidewall height provides a more comfortable ride by absorbing more road imperfections. Taller sidewalls also offer better protection against pothole damage to wheels. The trade-off is slightly less responsive steering feel.

Ground clearance: Increases by 18.2mm, providing slightly better approach angles for off-road driving and speed bump clearance.

Vehicles Using 225/55R18

Vehicles Using 235/55R19

Related Comparisons

Individual Tire Specs

Frequently Asked Questions

This swap is not recommended without modifications. The diameter difference is +5.17% (+36.4mm). This exceeds the recommended 3% threshold and may affect speedometer accuracy, ABS calibration, and could cause clearance issues.
Switching from 225/55R18 to 235/55R19 creates a +5.17% speedometer error. Your actual speed will be faster than displayed — at an indicated 60 mph, you'll actually be going 63.1 mph.
Switching from 225/55R18 to 235/55R19 changes ground clearance by +18.2mm. The vehicle will sit 18.2mm higher. Ground clearance change equals half the overall diameter difference.