I should be able to find this out somewhere, but I'm just curious.... does the Platinum XTS with 20 inch wheels have correspondingly larger brake rotors by any chance? I can't see why Cadillac would have higher production costs by having two different sizes of brakes, but I can't really see the point of offering huge 20 inch wheels/tires otherwise. Seems like a lot of un-necessary extra unsprung weight, and harsher ride, just for the prestige of being able to say that you have monster tires.
It's not for monster tires, it's for the bling. The rotors should be the same. FWIW, my CTS-V has 15" rotors! And I can fit 18" wheels on there. So, if Cadillac went for the minimalist look, I'm sure 17"s, maybe even 16"s could fit...
I am pretty sure the rotors are the same. The 20's do allow a bit more of the Brembos to show through plus they have a premium finish on the calipers.
But that brings up another point, actually so far one of the very few and very minor quibbles I have with my new XTS Platinum. They put some pretty nice wheels with polished aluminum and chrome inserts, but then decided to go with a black rubber TPMS valve stem and cap.
Why not go with a complimentary polished aluminum or chrome sleeve and cap?
Thanks. I know that is a problem with some match ups. Many of the "chrome" caps are actually abs with a chrome finish and a special o ring for seal. At any rate, we don't tend to have street salt in Las Vegas. If I put on chrome caps it will only be ones that are specially approved for the XTS OEM TPMS. My STS had chrome caps and never had any problem with the TPMS. Also some OEMs actually choose to go with metal TPMS valve stems and metal caps. I will see what evolves. My post was that I felt the black rubber just did not do the 20" Platinum wheels justice.
OK, earlier I commented on the 20" wheels on my XTS with the black rubber valve stems and that IMHO they were a slight distraction to the otherwise very nice wheels. Here is what SilverFox looked like initially:
and here is what I added today:
(that is not dirt on the wheel, but a reflection of my garage floor)