Tire Size Box

355/30R24 vs 345/35R24

345/35R24 compared with 355/30R24

+3.5% diameter, −0.4" width

345/35R24 is 33.51" tall vs 32.39". More than the 3% rule of thumb, so check carefully before switching.

32.4"24" rim4.2"14.0" wide
355/30R24 (solid) compared with 345/35R24 (dashed outline), drawn to scale

With 345/35R24 tires, when your speedometer says 60 mph you are really going

62.1 mph

345/35R24 is +1.12 inches (+3.5%) in overall diameter. That is more than the 3% most shops and makers recommend.

355/30R24345/35R24Difference%
Overall diameter32.39"33.51"+1.12"+3.5%
Section width13.98"13.58"−0.39"−2.8%
Sidewall height4.19"4.75"+0.56"+13.4%
Circumference101.74"105.27"+3.53"+3.5%
Revolutions per mile622.7601.9−20.9−3.3%

Speedometer difference

If your vehicle came with 355/30R24 and you fit 345/35R24, 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 mph41.4 mph+1.4 mph
50 mph51.7 mph+1.7 mph
60 mph62.1 mph+2.1 mph
65 mph67.3 mph+2.3 mph
70 mph72.4 mph+2.4 mph
75 mph77.6 mph+2.6 mph
80 mph82.8 mph+2.8 mph

Each size on its own

Questions

Which is bigger, 355/30R24 or 345/35R24?
345/35R24 is taller by 1.12 inches (33.51" vs 32.39"). 355/30R24 is wider by 0.39 inches.
Can I replace 355/30R24 with 345/35R24?
It is not recommended without checking carefully. The diameter difference is +3.5%, 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 345/35R24 change my speedometer?
When your speedometer reads 60 mph with 345/35R24 fitted (calibrated for 355/30R24), your real speed is 62.1 mph. Your odometer will under-count miles by about 3.5%.
Will 345/35R24 lift my vehicle?
Ride height changes by half the diameter difference: +0.56 inches of ground clearance at the axle.

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