Has anyone with a XF SC switched to 18" Wheels ? Noticed a difference is ride quality and mpg ? Thoughts ?

 

I thought there may be a problem with the size of the front brake rotors..

 

Which year SC do you have? 2010 and onwards SC and XFR have very large front brakes and it's near impossible to find a 19inch to fit. Doubt you could get any 18s of any sort on them. I looked for a long while for a 19inch for my winter wheels (2010 SC) but gave up and stuck with 20s as nothing seemed to fit (there are just a couple of 19inch jag wheels that apparently do fit if you search around the forum)

2009 I believe had a slightly smaller front brake caliper and you might have more luck there

Why do you want to shift down to 18inch?

 

2009 XF SC, I got a set of 18" Stock wheels that came with it. Im considering putting the 18" on due to the potholes in the region. I don't want to keep changing tires and repairing rims from these potholes. Thoughts ?

 

If you've already got the 18s just throw them on and try them.
I run 18s and I'd like 20s purely for aesthetic purposes, but the reality is on most shitty roads the 18's perform much better and are much more comfortable.

 

Yep, 18s will fit over the 355 mm front brake calipers on the 09 SC, but no chance they will fit over the 380 mm calipers on the XFR.

 

I hear you on the potholes - I live on the east coast too. Agree with comments above - if you have them already then put them on and see what you think

If I were you I'd put summer tyres on the 20inch and winter on the 18inch. Then swap over the wheels Nov and April. It's a really easy swap - will give you better traction all year round. And the 18s can take the pothole beating

I expect you'll feel a softer ride over poor roads in the 18s but doubt you'll see much in fuel economy. May save you a lot in wheel and tyre repairs though...