Tire Size Box

335/45R20 vs 335/50R20

335/50R20 compared with 335/45R20

+4.1% diameter, 0.0" width

335/50R20 is 33.19" tall vs 31.87". More than the 3% rule of thumb, so check carefully before switching.

31.9"20" rim5.9"13.2" wide
335/45R20 (solid) compared with 335/50R20 (dashed outline), drawn to scale

With 335/50R20 tires, when your speedometer says 60 mph you are really going

62.5 mph

335/50R20 is +1.32 inches (+4.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

335/45R20335/50R20Difference%
Overall diameter31.87"33.19"+1.32"+4.1%
Section width13.19"13.19"0.00"0.0%
Sidewall height5.94"6.59"+0.66"+11.1%
Circumference100.12"104.27"+4.14"+4.1%
Revolutions per mile632.8607.7−25.1−4.0%

Speedometer difference

If your vehicle came with 335/45R20 and you fit 335/50R20, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.2 mph+1.2 mph
40 mph41.7 mph+1.7 mph
50 mph52.1 mph+2.1 mph
60 mph62.5 mph+2.5 mph
65 mph67.7 mph+2.7 mph
70 mph72.9 mph+2.9 mph
75 mph78.1 mph+3.1 mph
80 mph83.3 mph+3.3 mph

Each size on its own

Questions

Which is bigger, 335/45R20 or 335/50R20?
335/50R20 is taller by 1.32 inches (33.19" vs 31.87"). 335/45R20 is the same width.
Can I replace 335/45R20 with 335/50R20?
It is not recommended without checking carefully. The diameter difference is +4.1%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 335/50R20 change my speedometer?
When your speedometer reads 60 mph with 335/50R20 fitted (calibrated for 335/45R20), your real speed is 62.5 mph. Your odometer will under-count miles by about 4.1%.
Will 335/50R20 lift my vehicle?
Ride height changes by half the diameter difference: +0.66 inches of ground clearance at the axle.

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