Tire Size Box

205/35R17 vs 205/45R17

205/45R17 compared with 205/35R17

+7.1% diameter, 0.0" width

205/45R17 is 24.26" tall vs 22.65". More than the 3% rule of thumb, so check carefully before switching.

22.6"17" rim2.8"8.1" wide
205/35R17 (solid) compared with 205/45R17 (dashed outline), drawn to scale

With 205/45R17 tires, when your speedometer says 60 mph you are really going

64.3 mph

205/45R17 is +1.61 inches (+7.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

205/35R17205/45R17Difference%
Overall diameter22.65"24.26"+1.61"+7.1%
Section width8.07"8.07"0.00"0.0%
Sidewall height2.82"3.63"+0.81"+28.6%
Circumference71.16"76.23"+5.07"+7.1%
Revolutions per mile890.4831.2−59.2−6.7%

Speedometer difference

If your vehicle came with 205/35R17 and you fit 205/45R17, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.4 mph+1.4 mph
30 mph32.1 mph+2.1 mph
40 mph42.9 mph+2.9 mph
50 mph53.6 mph+3.6 mph
60 mph64.3 mph+4.3 mph
65 mph69.6 mph+4.6 mph
70 mph75.0 mph+5.0 mph
75 mph80.3 mph+5.3 mph
80 mph85.7 mph+5.7 mph

Each size on its own

Questions

Which is bigger, 205/35R17 or 205/45R17?
205/45R17 is taller by 1.61 inches (24.26" vs 22.65"). 205/35R17 is the same width.
Can I replace 205/35R17 with 205/45R17?
It is not recommended without checking carefully. The diameter difference is +7.1%, 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 205/45R17 change my speedometer?
When your speedometer reads 60 mph with 205/45R17 fitted (calibrated for 205/35R17), your real speed is 64.3 mph. Your odometer will under-count miles by about 7.1%.
Will 205/45R17 lift my vehicle?
Ride height changes by half the diameter difference: +0.81 inches of ground clearance at the axle.

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