Tiresize comparison. 225/45 R17 vs 225/40 R18. Calculate. CM INCHES. If your speedometer reads: Real speed is: Size difference between 225/45 R17 and 225/40 R18 tires. In the tire comparison table above, you can
Thesidewall is only 3mm shorter for 245/40 compered to 225/45, that is about 1/8". But you also have the option to fit 245/45-18 which has 9mm (3/8") taller sidewalls than 225/45. Ah got it, thanks for the info! That little of a difference shouldn't impact ride quality much then. I run 245/40/18 currently for winter.23545-R18 tires are 0.35 inches (9 mm) larger in diameter than 225/45-R18 tires and the speedometer difference is 1.3%.
24535-R18 tires are 0.33 inches (8.5 mm) smaller in diameter than 225/40-R18 tires and the speedometer difference is 1.3%.
23560-R18 tires are 0.47 inches (12 mm) larger in diameter than 225/60-R18 tires and the speedometer difference is 1.6%.
Inthe tire comparison table above, you can see a detailed calculation of the size difference between 225/55 R17 and 245/45 R18 tire. The calculation results are presented in the form of visual infographics, on which tire with size 225/55 R17 is on top, and tire with size 245/45 R18 below. Both in the table and in the graph, the tires are
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