265/50R20 vs 275/55R20 Side-by-side tire size comparison with specs and compatibility

265/50R20⌀ 773mm275/55R20⌀ 811mm+18.8mm
Compatibility
+4.85% diameter difference
⚠ Swap with Caution

This tire swap is between 3-5% diameter difference. Check for fender clearance and be aware of speedometer error. May require recalibration.

Full Specifications Comparison

Specification 265/50R20 275/55R20 Difference
Overall Diameter 773 mm (30.4") 810.5 mm (31.9") +37.5 mm
Section Width 265 mm (10.4") 275 mm (10.8") +10 mm
Sidewall Height 132.5 mm 151.3 mm +18.8 mm
Circumference 2428.5 mm 2546.3 mm +117.8 mm
Revolutions/Mile 663 632 -31
Aspect Ratio 50% 55% +5%
Rim Diameter 20" 20" 0"

Key Impact Summary

Ground Clearance
+18.8 mm
Speedometer Error
+4.85%
Width Change
+10 mm
Sidewall Change
+18.8 mm

Speedometer Correction Table

When switching from 265/50R20 to 275/55R20, 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 41.9 mph +1.9 mph
50 mph 52.4 mph +2.4 mph
60 mph 62.9 mph +2.9 mph
70 mph 73.4 mph +3.4 mph
80 mph 83.9 mph +3.9 mph
90 mph 94.4 mph +4.4 mph
100 mph 104.9 mph +4.9 mph
110 mph 115.3 mph +5.3 mph
120 mph 125.8 mph +5.8 mph

What This Swap Means

Wider tires (275/55R20): 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 18.8mm 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 18.8mm, providing slightly better approach angles for off-road driving and speed bump clearance.

Vehicles Using 265/50R20

Vehicles Using 275/55R20

Related Comparisons

Individual Tire Specs

Frequently Asked Questions

This swap requires caution. The diameter difference is +4.85% (+37.5mm). This exceeds the recommended 3% threshold and may affect speedometer accuracy, ABS calibration, and could cause clearance issues.
Switching from 265/50R20 to 275/55R20 creates a +4.85% speedometer error. Your actual speed will be faster than displayed — at an indicated 60 mph, you'll actually be going 62.9 mph.
Switching from 265/50R20 to 275/55R20 changes ground clearance by +18.8mm. The vehicle will sit 18.8mm higher. Ground clearance change equals half the overall diameter difference.