Tire Size Box

275/45R17 vs 275/50R17

275/50R17 compared with 275/45R17

+4.0% diameter, 0.0" width

275/50R17 is 27.83" tall vs 26.74". More than the 3% rule of thumb, so check carefully before switching.

26.7"17" rim4.9"10.8" wide
275/45R17 (solid) compared with 275/50R17 (dashed outline), drawn to scale

With 275/50R17 tires, when your speedometer says 60 mph you are really going

62.4 mph

275/50R17 is +1.08 inches (+4.0%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/45R17275/50R17Difference%
Overall diameter26.74"27.83"+1.08"+4.0%
Section width10.83"10.83"0.00"0.0%
Sidewall height4.87"5.41"+0.54"+11.1%
Circumference84.02"87.42"+3.40"+4.0%
Revolutions per mile754.1724.8−29.3−3.9%

Speedometer difference

If your vehicle came with 275/45R17 and you fit 275/50R17, 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 mph41.6 mph+1.6 mph
50 mph52.0 mph+2.0 mph
60 mph62.4 mph+2.4 mph
65 mph67.6 mph+2.6 mph
70 mph72.8 mph+2.8 mph
75 mph78.0 mph+3.0 mph
80 mph83.2 mph+3.2 mph

Each size on its own

Questions

Which is bigger, 275/45R17 or 275/50R17?
275/50R17 is taller by 1.08 inches (27.83" vs 26.74"). 275/45R17 is the same width.
Can I replace 275/45R17 with 275/50R17?
It is not recommended without checking carefully. The diameter difference is +4.0%, 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 275/50R17 change my speedometer?
When your speedometer reads 60 mph with 275/50R17 fitted (calibrated for 275/45R17), your real speed is 62.4 mph. Your odometer will under-count miles by about 4.0%.
Will 275/50R17 lift my vehicle?
Ride height changes by half the diameter difference: +0.54 inches of ground clearance at the axle.

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