Minimum difference in tire height Front to BacK

[GordonB]

Have searched and read most of the Tire Sticky posts as well as the referenced links, but haven't found the one key measurement. OEM Tire height difference is 1.3" front to back -- the REAR BFGs 245/55 R18 are 1.3" (28.5"dia) higher than the FRONT BFGs 235/50 R18 (27.2" dia.)

Question: to keep the Traction Control and the ABS happy :), what is the MINIMUM height difference that must be maintained regardless of whose tires, size, profile, etc. we buy?

Thanks for the input.

GordonB

[Bluerauder]

Have searched and read most of the Tire Sticky posts as well as the referenced links, but haven't found the one key measurement. OEM Tire height difference is 1.3" front to back -- the REAR BFGs 245/55 R18 are 1.3" (28.5"dia) higher than the FRONT BFGs 235/50 R18 (27.2" dia.)

Question: to keep the Traction Control and the ABS happy :), what is the MINIMUM height difference that must be maintained regardless of whose tires, size, profile, etc. we buy?

Thanks for the input.

GordonB
The OEM difference ratio of rears to fronts is 28.61"/27.25" = 1.0499 (or 4.99% ~ 5% more). The generally accepted range difference is 2.0% (on the low side) to 6.6% (on the high side). So the minimum rear tire height would be about 27.80" and the maximum would be about 29.05". The 255/55/18 is the max rear size with the OEM 235/50/18 fronts (+6.6%). I am running the 255/55/18 Rears & 235/50/18 Fronts on my 300B.

Theoretically, the minimum height difference would be 0.55" but I would allow at least another 0.25" to account for any wear difference between new rears and old front or vice versa. (minimum of 0.80" height difference). Does this make sense to you?

[GordonB]

Charlie,
The 0.8 inches makes perfect sense.
Thank you for posting the details of the % difference.
Gordonb