I am thinking about putting 18's on my g/f's XB Whats the biggest tire i can run with out rubbing? ANd whats the biggest I can run on 17's? I appreciate all the help I can get..... Just got ours yesterday and she loves it.

The learget tire i have seen on a 17 is a 215/45R17. I currently have those installed on my xB.

this will help you

http://www.scionlife.com/forums/viewtopic.php?t=348

I went to a tire calculator site, and here's what I came up with. In order to keep the stock speedo reading as accurate as possible, using a 185/60-15 stock tire size, these are the sizes you need to get:

225/45-17
215/35-18

The 215/35-18 is pretty close to the stock overall tire/wheel diameter, while the 225-45-17 is just a tad bigger. I have the 215/35-18 combo, and the car still needs lowering springs to take up some of that wheel well gap, which is almost at 3". Had I been able to choose the tire size, I would've went with 225/35-18s, and with TRD springs, that 3" gap should be reduced by about half.

215-315-18 is whaat im runnin

Have 2 xB's. can be seen in gallery.
thunder cloud is running 18x7.5 w 215/35/18 " khumo's (ecsta) panther voltaic wheels 35 offset
hot lava is running 18x8.0 w 215/40/18 " falken's (451) Metal FX wheels 40 offset

the hot lava 's tire's rub just a little bit . i've read about people cutting the plastic inner fenderwell to avoid this.does not bother me ,as it only occurs during sharp turning radius.

don't recomend 215/35's. lousy ride ,much regret !! the less sidewall you have the harsher the ride !!!

remember 215 =width/40= tall/ 18= diameter.

as far as 17"s , should be able to go with a taller tire. Width of tire depends on width of wheel ???

the offset of any wheel you get also is a factor .ck this websight to get info.

http://www.discountedwheelwarehouse.com/Wheel_Fitment_Guide.cfm

hope this helps.

hotlava1886