Tire Size Box

295/40R17 vs 295/50R17

295/50R17 compared with 295/40R17

+8.8% diameter, 0.0" width

295/50R17 is 28.61" tall vs 26.29". More than the 3% rule of thumb, so check carefully before switching.

26.3"17" rim4.6"11.6" wide
295/40R17 (solid) compared with 295/50R17 (dashed outline), drawn to scale

With 295/50R17 tires, when your speedometer says 60 mph you are really going

65.3 mph

295/50R17 is +2.32 inches (+8.8%) in overall diameter. That is more than the 3% most shops and makers recommend.

295/40R17295/50R17Difference%
Overall diameter26.29"28.61"+2.32"+8.8%
Section width11.61"11.61"0.00"0.0%
Sidewall height4.65"5.81"+1.16"+25.0%
Circumference82.60"89.89"+7.30"+8.8%
Revolutions per mile767.1704.8−62.3−8.1%

Speedometer difference

If your vehicle came with 295/40R17 and you fit 295/50R17, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.8 mph+1.8 mph
30 mph32.7 mph+2.7 mph
40 mph43.5 mph+3.5 mph
50 mph54.4 mph+4.4 mph
60 mph65.3 mph+5.3 mph
65 mph70.7 mph+5.7 mph
70 mph76.2 mph+6.2 mph
75 mph81.6 mph+6.6 mph
80 mph87.1 mph+7.1 mph

Each size on its own

Questions

Which is bigger, 295/40R17 or 295/50R17?
295/50R17 is taller by 2.32 inches (28.61" vs 26.29"). 295/40R17 is the same width.
Can I replace 295/40R17 with 295/50R17?
It is not recommended without checking carefully. The diameter difference is +8.8%, 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 295/50R17 change my speedometer?
When your speedometer reads 60 mph with 295/50R17 fitted (calibrated for 295/40R17), your real speed is 65.3 mph. Your odometer will under-count miles by about 8.8%.
Will 295/50R17 lift my vehicle?
Ride height changes by half the diameter difference: +1.16 inches of ground clearance at the axle.

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