Tire Size Box

335/40R19 vs 335/45R19

335/45R19 compared with 335/40R19

+4.5% diameter, 0.0" width

335/45R19 is 30.87" tall vs 29.55". More than the 3% rule of thumb, so check carefully before switching.

29.6"19" rim5.3"13.2" wide
335/40R19 (solid) compared with 335/45R19 (dashed outline), drawn to scale

With 335/45R19 tires, when your speedometer says 60 mph you are really going

62.7 mph

335/45R19 is +1.32 inches (+4.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

335/40R19335/45R19Difference%
Overall diameter29.55"30.87"+1.32"+4.5%
Section width13.19"13.19"0.00"0.0%
Sidewall height5.28"5.94"+0.66"+12.5%
Circumference92.84"96.98"+4.14"+4.5%
Revolutions per mile682.5653.3−29.2−4.3%

Speedometer difference

If your vehicle came with 335/40R19 and you fit 335/45R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.9 mph+0.9 mph
30 mph31.3 mph+1.3 mph
40 mph41.8 mph+1.8 mph
50 mph52.2 mph+2.2 mph
60 mph62.7 mph+2.7 mph
65 mph67.9 mph+2.9 mph
70 mph73.1 mph+3.1 mph
75 mph78.3 mph+3.3 mph
80 mph83.6 mph+3.6 mph

Each size on its own

Questions

Which is bigger, 335/40R19 or 335/45R19?
335/45R19 is taller by 1.32 inches (30.87" vs 29.55"). 335/40R19 is the same width.
Can I replace 335/40R19 with 335/45R19?
It is not recommended without checking carefully. The diameter difference is +4.5%, 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 335/45R19 change my speedometer?
When your speedometer reads 60 mph with 335/45R19 fitted (calibrated for 335/40R19), your real speed is 62.7 mph. Your odometer will under-count miles by about 4.5%.
Will 335/45R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.66 inches of ground clearance at the axle.

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