Tire Size Box

295/40R19 vs 295/45R19

295/45R19 compared with 295/40R19

+4.1% diameter, 0.0" width

295/45R19 is 29.45" tall vs 28.29". More than the 3% rule of thumb, so check carefully before switching.

28.3"19" rim4.6"11.6" wide
295/40R19 (solid) compared with 295/45R19 (dashed outline), drawn to scale

With 295/45R19 tires, when your speedometer says 60 mph you are really going

62.5 mph

295/45R19 is +1.16 inches (+4.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

295/40R19295/45R19Difference%
Overall diameter28.29"29.45"+1.16"+4.1%
Section width11.61"11.61"0.00"0.0%
Sidewall height4.65"5.23"+0.58"+12.5%
Circumference88.88"92.53"+3.65"+4.1%
Revolutions per mile712.9684.8−28.1−3.9%

Speedometer difference

If your vehicle came with 295/40R19 and you fit 295/45R19, 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 mph52.1 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, 295/40R19 or 295/45R19?
295/45R19 is taller by 1.16 inches (29.45" vs 28.29"). 295/40R19 is the same width.
Can I replace 295/40R19 with 295/45R19?
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 295/45R19 change my speedometer?
When your speedometer reads 60 mph with 295/45R19 fitted (calibrated for 295/40R19), your real speed is 62.5 mph. Your odometer will under-count miles by about 4.1%.
Will 295/45R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.58 inches of ground clearance at the axle.

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