I want to put some rims on my xB but am a little confused. I was told that 18's are too big and will trash my trany. Is this true? If so I'm looking for a set of 17" black rims, something that not everybody else is rolling on.[/b]

 

I have a friend w/ 20" on his xB so size depends on how worried you around about the additional weight it might add to the suspension/drivetrain.

I recommend checking out the link at the top of this forum for specific sizes and etc..
https://www.scionlife.com/forums/viewtopic.php?t=348

 

There is no real difference as far as the car is concerned between using 18inch or 17 inch or even 15 inch rims (besides the look). The overall diameter of the wheel and tire assembly should be the same for proper speedo function and so as not to change final drive ratios. The weight of the wheel and tire combo can be an issue. Lighter is generally better in all cases. If you like the look of 18" then do it. I certainly wouldn't worry about the transmission unless you use very very heavy wheels. You do need to be concerned with wheel width and offset to ensure that they don't rub on stuff.

 

Good advice, if you have the fitment correct, the increased weight would be the biggest impacting factor!

 

if that was true then Toyota wouldn't offer TRD 18" as a factory upgrade

 

You won't have problems with your tranny. The ride quality might go to hell though.