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Tire size comparisons · Updated

285/40R22 vs 285/45R22

Check clearance and speedometer: the 285/45R22 is 3.6% taller than the 285/40R22.

Check clearance and speedometer. 285/45R22 is 3.6% taller than 285/40R22 (+1.12 in, 31.0 to 32.1 in). 60 mph on the speedometer is really 62.2 mph and the ride height changes by about +0.56 in.

285/40R22 vs 285/45R22 at a glance

285/40R22 and 285/45R22 compared
Measure285/40R22 (current)285/45R22 (new)Difference
Overall height30.98 in32.10 in+1.12 in (+3.62%)
Width11.22 in (285 mm)11.22 in (285 mm)+0 mm
Sidewall4.49 in5.05 in+0.56 in
Wheel22 in22 in+0 in
Circumference97.3 in100.8 in+3.5 in
Revs per mile651.1628.3−22.8

Verdict: check clearance and speedometer

Over 3% and up to 5%: worth checking clearance, the speedometer and gearing before you buy. Going from 285/40R22 to 285/45R22 is a 3.6% increase in overall height (+1.12 in), and the vehicle sits about 0.56 in higher. The tire is the same width. The 3% rule of thumb comes from Discount Tire and 1010tires; it is not a guarantee of fit.

True speed and odometer

Speedometer after swapping 285/40R22 for 285/45R22
Speedometer showsYou are really doingDifference
35 mph36.3 mph+1.3 mph
45 mph46.6 mph+1.6 mph
55 mph57.0 mph+2.0 mph
60 mph62.2 mph+2.2 mph
65 mph67.4 mph+2.4 mph
70 mph72.5 mph+2.5 mph
75 mph77.7 mph+2.7 mph

Odometer: 1,000 indicated miles is 1,036 real miles, and 10,000 is 10,362.

The math

285/40R22: 22 + 2 × (285 × 40% ÷ 25.4) = 30.98 in. 285/45R22: 22 + 2 × (285 × 45% ÷ 25.4) = 32.10 in. Change = 32.10 ÷ 30.98 − 1 = +3.62%. True speed at 60 = 60 × 32.10 ÷ 30.98 = 62.17 mph.

Check next

Calculated from the size alone. Real tires vary a little by brand and model, and the loaded radius is a bit smaller. Confirm the wheel width range, clearance, load index and speed rating for your vehicle. See how to read a tire size, the load index chart and the speed rating chart.

Size pages: 285/40R22 · 285/45R22. More swaps: all tire size comparisons.

FAQ

Is 285/45R22 bigger than 285/40R22?

285/45R22 is 32.10 in tall against 30.98 in, so it is 3.6% taller and the same width.

What is my real speed with 285/45R22 instead of 285/40R22?

60 mph on the speedometer is really 62.2 mph and 70 is 72.5 mph.

Will 285/45R22 fit where 285/40R22 fits?

It is a check clearance and speedometer on height (+3.6%). Fit also depends on wheel width, offset, clearance, load index and speed rating: this cannot tell you.

How much will the ride height change from 285/40R22 to 285/45R22?

About 0.56 in higher, half of the 1.12 in change in tire height.

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