Tire Size Box

295/30R19 vs 295/40R19

295/40R19 compared with 295/30R19

+8.9% diameter, 0.0" width

295/40R19 is 28.29" tall vs 25.97". More than the 3% rule of thumb, so check carefully before switching.

26.0"19" rim3.5"11.6" wide
295/30R19 (solid) compared with 295/40R19 (dashed outline), drawn to scale

With 295/40R19 tires, when your speedometer says 60 mph you are really going

65.4 mph

295/40R19 is +2.32 inches (+8.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

295/30R19295/40R19Difference%
Overall diameter25.97"28.29"+2.32"+8.9%
Section width11.61"11.61"0.00"0.0%
Sidewall height3.48"4.65"+1.16"+33.3%
Circumference81.58"88.88"+7.30"+8.9%
Revolutions per mile776.6712.9−63.8−8.2%

Speedometer difference

If your vehicle came with 295/30R19 and you fit 295/40R19, 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 mph43.6 mph+3.6 mph
50 mph54.5 mph+4.5 mph
60 mph65.4 mph+5.4 mph
65 mph70.8 mph+5.8 mph
70 mph76.3 mph+6.3 mph
75 mph81.7 mph+6.7 mph
80 mph87.2 mph+7.2 mph

Each size on its own

Questions

Which is bigger, 295/30R19 or 295/40R19?
295/40R19 is taller by 2.32 inches (28.29" vs 25.97"). 295/30R19 is the same width.
Can I replace 295/30R19 with 295/40R19?
It is not recommended without checking carefully. The diameter difference is +8.9%, 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 295/40R19 change my speedometer?
When your speedometer reads 60 mph with 295/40R19 fitted (calibrated for 295/30R19), your real speed is 65.4 mph. Your odometer will under-count miles by about 8.9%.
Will 295/40R19 lift my vehicle?
Ride height changes by half the diameter difference: +1.16 inches of ground clearance at the axle.

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