Tire Size Box

335/25R19 vs 315/30R19

315/30R19 compared with 335/25R19

+3.3% diameter, −0.8" width

315/30R19 is 26.44" tall vs 25.59". More than the 3% rule of thumb, so check carefully before switching.

25.6"19" rim3.3"13.2" wide
335/25R19 (solid) compared with 315/30R19 (dashed outline), drawn to scale

With 315/30R19 tires, when your speedometer says 60 mph you are really going

62.0 mph

315/30R19 is +0.85 inches (+3.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

335/25R19315/30R19Difference%
Overall diameter25.59"26.44"+0.85"+3.3%
Section width13.19"12.40"−0.79"−6.0%
Sidewall height3.30"3.72"+0.42"+12.8%
Circumference80.41"83.07"+2.66"+3.3%
Revolutions per mile788.0762.8−25.2−3.2%

Speedometer difference

If your vehicle came with 335/25R19 and you fit 315/30R19, 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 mph67.1 mph+2.1 mph
70 mph72.3 mph+2.3 mph
75 mph77.5 mph+2.5 mph
80 mph82.6 mph+2.6 mph

Each size on its own

Questions

Which is bigger, 335/25R19 or 315/30R19?
315/30R19 is taller by 0.85 inches (26.44" vs 25.59"). 335/25R19 is wider by 0.79 inches.
Can I replace 335/25R19 with 315/30R19?
It is not recommended without checking carefully. The diameter difference is +3.3%, 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 315/30R19 change my speedometer?
When your speedometer reads 60 mph with 315/30R19 fitted (calibrated for 335/25R19), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.3%.
Will 315/30R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.42 inches of ground clearance at the axle.

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