SidewallerTire & wheel calculators

225/35R20 vs 255/40R20

255/40R20 is 7.0% taller (+1.83 in) and 1.18 in wider than 225/35R20.

Large
Big change

255/40R20 is 7.0% taller than 225/35R20. Beyond 5% you usually need a lift or leveling kit, a speedometer recalibration and sometimes new gears.

225/35R20255/40R20Change
Diameter26.20″28.03″+1.83″+7.0%
Width8.86″10.04″+1.18″+13.3%
Sidewall3.10″4.02″+0.92″+29.5%
Circumference82.3″88.1″+5.8″+7.0%
Wheel20″20″Same
Revs per mile770719−50
SideTread
225/35R20255/40R20
Speedometer shows 60 mph64.2mph

Real speed on 255/40R20.

Ground clearance+0.92in

Change in height under the axle.

Width per side+0.59in

On the same wheel, split inboard and outboard.

Shop 255/40R20 tires

Opens the store’s own search

Prices and stock change often, so check a few stores. We don’t earn anything from these links.

225/35R20 or 255/40R20?

Can I use 255/40R20 instead of 225/35R20?

255/40R20 is 7.0% taller than 225/35R20. Beyond 5% you usually need a lift or leveling kit, a speedometer recalibration and sometimes new gears. Also match or beat the original load index and speed rating, and check that the wheel width suits the new tire.

Will my speedometer be off?

At an indicated 60 mph on 255/40R20 you are really doing 64.2 mph if the speedometer was set up for 225/35R20. Going the other way, 225/35R20 would make it read 56.1 mph at a real 60.

How much ground clearance does it change?

Half the diameter difference: +0.92 in (+23 mm) under the axle.

Other comparisons