265/35R18 vs 275/35R18 Side-by-side tire size comparison with specs and compatibility

265/35R18⌀ 643mm275/35R18⌀ 650mm+3.5mm
Compatibility
+1.09% diameter difference
✓ Safe Swap

This tire swap is within the safe 3% diameter threshold. It should not cause issues with speedometer accuracy, ABS, or traction control systems.

Full Specifications Comparison

Specification 265/35R18 275/35R18 Difference
Overall Diameter 642.7 mm (25.3") 649.7 mm (25.6") +7 mm
Section Width 265 mm (10.4") 275 mm (10.8") +10 mm
Sidewall Height 92.8 mm 96.3 mm +3.5 mm
Circumference 2019.1 mm 2041.1 mm +22 mm
Revolutions/Mile 797 788 -9
Aspect Ratio 35% 35% 0%
Rim Diameter 18" 18" 0"

Key Impact Summary

Ground Clearance
+3.5 mm
Speedometer Error
+1.09%
Width Change
+10 mm
Sidewall Change
+3.5 mm

Speedometer Correction Table

When switching from 265/35R18 to 275/35R18, your speedometer will under-read. Here is the correction at common speeds:

Speedometer Shows Actual Speed (mph) Difference
30 mph 30.3 mph +0.3 mph
40 mph 40.4 mph +0.4 mph
50 mph 50.5 mph +0.5 mph
60 mph 60.7 mph +0.7 mph
70 mph 70.8 mph +0.8 mph
80 mph 80.9 mph +0.9 mph
90 mph 91 mph +1 mph
100 mph 101.1 mph +1.1 mph
110 mph 111.2 mph +1.2 mph
120 mph 121.3 mph +1.3 mph

What This Swap Means

Wider tires (275/35R18): 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 3.5mm 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 3.5mm, providing slightly better approach angles for off-road driving and speed bump clearance.

Related Comparisons

Individual Tire Specs

Frequently Asked Questions

Yes, this swap is generally safe. The diameter difference is +1.09% (+7mm). This is within the safe 3% threshold and should not significantly affect your speedometer, ABS, or traction control.
Switching from 265/35R18 to 275/35R18 creates a +1.09% speedometer error. Your actual speed will be faster than displayed — at an indicated 60 mph, you'll actually be going 60.7 mph.
Switching from 265/35R18 to 275/35R18 changes ground clearance by +3.5mm. The vehicle will sit 3.5mm higher. Ground clearance change equals half the overall diameter difference.