Tire Sizing

[reddogsecurity]

I like running the FPIU in my security company versus the base explorer. The only issue I have is that we dont do high speed driving, we are slow, and many times at construction sites. I wouldnt mind putting larger tires on as the low profiles wear out, but I do not want to mess up the gearing and do not need any rubbing.

Pratical advice?

I am an offroader and always regear my rigs for the tire size and slower speeds. Probably wont get this in depth with company cars but dont want to hurt the torque at the slower speeds we use the most.

 

[peterk9]

Welcome to the Forum.
The generally accepted rule of thumb is not exceed the maximum diameter size of the OEM by more than 3%.
If the OEM is 245/60R18 then you could use 255/60R18 or 255/55R18.
Use this chart and plug in the OEM size in the original part and the desired size in the lower part and it will calculate everything for you.

245/60 R18 vs 255/55 R18 Tire Size Comparison Table with Graphic Visualization (inch difference)

The difference in sizes and parameters between the 245/60 R18 tire and 255/55 R18 tire. Detailed calculations and graphics. Calculate the difference in inches.

tire-calc.com

Peter

 

[throgmo]

55 series was low-profile in the Seventies. It's tall now.

If you wanted to be "practical", the idea of messing with the OEM-size tires wouldn't have occured to you. Leaving it stock is the sensible thing to do. But big tires will (to some) look cool. So go ahead and do it.