I bought a set of 21" Pirelli winter tires for my 2012 S. When trying to reset the TPMS settings, it only shows a 20" option for the winter tires. Any ways to get around this, or should I just set up as 21" summer tires?

 

I would set it to whatever pirelli recommends

 

Im having the same problem with my 04 CTT, i have 255/55/18 Winter tires and the only option for winters in the MID is 235/60/18.

I have heard that if you go to the dealer they can program new sizes into the computer with the PIWIS.

I am going to try that once i have my Cayenne going for the winter.