300DTurbo

Stock: 255/50/R19 XL
http://www.michelinman.com/tire-sele...55/50/19/tires

This is what I want: 255/60/R19
http://www.michelinman.com/tire-sele...55/60/19/tires



I did this about 4 years ago on another SUV of mine and I noticed a smoother ride.

Any takers? Anyone done this? Any physics buffs that can guide me one way or another?


thanks`

another_geek

It would fit but with the following caveats:

1. Your car will sit 2" taller than currently
2. Your speedometer will be off by 7% (will show 60 mph when actually travelling @ 64mph). Your odometer will be off by same %

MLee

255 50. Sidewall profile height would be 127.5 mm

255 60 Would be. 153.0 mm

Car would sit 25.5 mm higher....... One inch. Not two.
If your speedo currently reads the average 4 or 5% above actual speed, then it might
just about be spot on with the larger tyre.

another_geek

true, radius (sidewall) would be 25mm greater, but the diameter (height) of the tire is 2 x radius, so 2" taller, not 1"

MLee

Sorry to give you the bad news, but the vehicle height is only altered by the change in radius. A 2 inch larger diameter wheel will only lift the vehicle height by 1 inch.
The vehicle is supported by the axle in the centre of the wheel......not the top of the wheel. Hence, distance from the centre of the wheel to the ground is what counts........that would be the radius. Result = 1 inch

Cheers

another_geek

Gotcha. My bad. Forgot about that