Tire Size Box

345/40R19 vs 335/45R19

335/45R19 compared with 345/40R19

+3.4% diameter, −0.4" width

335/45R19 is 30.87" tall vs 29.87". More than the 3% rule of thumb, so check carefully before switching.

29.9"19" rim5.4"13.6" wide
345/40R19 (solid) compared with 335/45R19 (dashed outline), drawn to scale

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

62.0 mph

335/45R19 is +1.00 inches (+3.4%) in overall diameter. That is more than the 3% most shops and makers recommend.

345/40R19335/45R19Difference%
Overall diameter29.87"30.87"+1.00"+3.4%
Section width13.58"13.19"−0.39"−2.9%
Sidewall height5.43"5.94"+0.50"+9.2%
Circumference93.83"96.98"+3.15"+3.4%
Revolutions per mile675.3653.3−22.0−3.3%

Speedometer difference

If your vehicle came with 345/40R19 and you fit 335/45R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.0 mph+1.0 mph
40 mph41.3 mph+1.3 mph
50 mph51.7 mph+1.7 mph
60 mph62.0 mph+2.0 mph
65 mph67.2 mph+2.2 mph
70 mph72.4 mph+2.4 mph
75 mph77.5 mph+2.5 mph
80 mph82.7 mph+2.7 mph

Each size on its own

Questions

Which is bigger, 345/40R19 or 335/45R19?
335/45R19 is taller by 1.00 inches (30.87" vs 29.87"). 345/40R19 is wider by 0.39 inches.
Can I replace 345/40R19 with 335/45R19?
It is not recommended without checking carefully. The diameter difference is +3.4%, 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 345/40R19), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.4%.
Will 335/45R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.50 inches of ground clearance at the axle.

Other comparisons