Tire Size Box

275/35R19 vs 275/45R19

275/45R19 compared with 275/35R19

+8.1% diameter, 0.0" width

275/45R19 is 28.74" tall vs 26.58". More than the 3% rule of thumb, so check carefully before switching.

26.6"19" rim3.8"10.8" wide
275/35R19 (solid) compared with 275/45R19 (dashed outline), drawn to scale

With 275/45R19 tires, when your speedometer says 60 mph you are really going

64.9 mph

275/45R19 is +2.17 inches (+8.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/35R19275/45R19Difference%
Overall diameter26.58"28.74"+2.17"+8.1%
Section width10.83"10.83"0.00"0.0%
Sidewall height3.79"4.87"+1.08"+28.6%
Circumference83.50"90.30"+6.80"+8.1%
Revolutions per mile758.8701.6−57.2−7.5%

Speedometer difference

If your vehicle came with 275/35R19 and you fit 275/45R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.6 mph+1.6 mph
30 mph32.4 mph+2.4 mph
40 mph43.3 mph+3.3 mph
50 mph54.1 mph+4.1 mph
60 mph64.9 mph+4.9 mph
65 mph70.3 mph+5.3 mph
70 mph75.7 mph+5.7 mph
75 mph81.1 mph+6.1 mph
80 mph86.5 mph+6.5 mph

Each size on its own

Questions

Which is bigger, 275/35R19 or 275/45R19?
275/45R19 is taller by 2.17 inches (28.74" vs 26.58"). 275/35R19 is the same width.
Can I replace 275/35R19 with 275/45R19?
It is not recommended without checking carefully. The diameter difference is +8.1%, 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 275/45R19 change my speedometer?
When your speedometer reads 60 mph with 275/45R19 fitted (calibrated for 275/35R19), your real speed is 64.9 mph. Your odometer will under-count miles by about 8.1%.
Will 275/45R19 lift my vehicle?
Ride height changes by half the diameter difference: +1.08 inches of ground clearance at the axle.

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