I know they come with 215/35 18s but I really need to get some more sidewall due to all of the friggin' potholes and bumps in Chicago!
I wanna keep the same width, so does that mean I can step up to a 215/40 18 without a rubbbing issue? How much more sidewall will that give me? Anyone have pics of the 215/40 18 on their Box?

Btw, I'm lowered on H Techs...

 

okay, now correct me if i am wrong, but 215 is the width of the tire in millimeters, and 35 is the height of the tire expressed as a percentage of the width? right?

so 215/35/18 is 75.25 millimeters, and 215/40/18 would be 86 millimeters, so the difference is 10.75 millimeters. does that sound like enough to cause rubbing?

 

oh, but your speedometer and odometer will be off, so you'll have to recalibrate that.

 

Does modifying wheel/tire size from the stock size make THAT big of a difference in the calibration of speedometer/odometer? And should one make it a point to have those recalibrated once new, larger wheels/tires are put on? I'm asking before i decide to get larger ones for my box.
Thanks

 

Here ya go. 215/40/18 is gonna give you 1/2 inch more of sidwall roughly. Just forget about lowering it or using rear spacers.
Here is a wheel/tire calculator link. Have fun...
http://www.rims-n-tires.com/rt_specs.jsp?postId=906

 

If you want more sidewall, you would be better going with a 17....the 18s definitely have the skinny sidewalls, but the 40 series will be fine, just remember they are taller when you cut the wheel sharply, you might rub a bit since you are lowered