Tire Size Box

275/40R16 vs 275/50R16

275/50R16 compared with 275/40R16

+8.8% diameter, 0.0" width

275/50R16 is 26.83" tall vs 24.66". More than the 3% rule of thumb, so check carefully before switching.

24.7"16" rim4.3"10.8" wide
275/40R16 (solid) compared with 275/50R16 (dashed outline), drawn to scale

With 275/50R16 tires, when your speedometer says 60 mph you are really going

65.3 mph

275/50R16 is +2.17 inches (+8.8%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/40R16275/50R16Difference%
Overall diameter24.66"26.83"+2.17"+8.8%
Section width10.83"10.83"0.00"0.0%
Sidewall height4.33"5.41"+1.08"+25.0%
Circumference77.48"84.28"+6.80"+8.8%
Revolutions per mile817.8751.8−66.0−8.1%

Speedometer difference

If your vehicle came with 275/40R16 and you fit 275/50R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.8 mph+1.8 mph
30 mph32.6 mph+2.6 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 mph76.1 mph+6.1 mph
75 mph81.6 mph+6.6 mph
80 mph87.0 mph+7.0 mph

Each size on its own

Questions

Which is bigger, 275/40R16 or 275/50R16?
275/50R16 is taller by 2.17 inches (26.83" vs 24.66"). 275/40R16 is the same width.
Can I replace 275/40R16 with 275/50R16?
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 275/50R16 change my speedometer?
When your speedometer reads 60 mph with 275/50R16 fitted (calibrated for 275/40R16), your real speed is 65.3 mph. Your odometer will under-count miles by about 8.8%.
Will 275/50R16 lift my vehicle?
Ride height changes by half the diameter difference: +1.08 inches of ground clearance at the axle.

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