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Stock tires front: 255/40/19 = 27.03"
Alternative front: 265/35/19 = 26.30"

Stock tires rear : 285/35/19 = 26.85"
Alternative rear : 295/30/19 = 25.96"

Rolling diameters are shorter and much shorter for the rears which will not be as significant in relevence to affecting ABS and speedometer accuracy. With shorter rolling diameters your topend speed will be compromised a bit and low end picked up a bit. This can be considered a "poor man's" diff. ratio change.

Equation used to calculate rolling diameter: tread width x sidewall profile diveded by 25.4 x 2 + rim diameter = rolling diameter.
ex. 255 / 40 / 19
255 x .4= 102 then divide by 25.4(to convert mm to inches)= 4.01, then multiply by 2(upper & lower sidewalls)= 8.03, then add 19(rim diameter in inches) = 27.03 inch rolling diameter.

Hope this makes sense. :)

Great information Ranger - thanks for that! So, if the car has been lowered (H&R Springs), would there be a chance of running into issues with these sizes? May not be able to answer that, but just wondering.
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