41 psi is fine from my experience with 20" pirellis on the f-type. I run the same or even one or two psi more. The manual says 41 psi for extended 155+ speeds. If it is good enough for the autobahn it is good enough for I-90.

 

Hi new to forum but my 2013 xjl rides so bumpy and stiff dont know if because the dynamic not working please help!!!! How to diagnose the problem

 

I recently had my tires changed and in doing so they jacked up one side of the car with air bags, following this the ride was as if stuck in dynamic. I checked it with a code checker and sure enough it was showing a fault. Resetting the code fixed the problem.

 

Interesting thread. The 2012 XJ I just purchased has the best ride of the three I test drove over the last 12 months :-

2011 XJ SWB
2012 XJ SWB
2013 XJ 2013

The 2013 is supposed to have an improved ride over the earlier models. Not true for the example I drove.

Of course, what I don't know is what pressures were set in each vehicle except for the one I own. At the standard 32 PSI my XJ rides superbly on the Nexen Nfera SU1 tyres the previous owner fitted shortly before selling it. The other two rode on the OEM Pirellis.

Tyre pressures can be an issue here in the US as most mechanics seem reluctant to inflate to less than 35 PSI. Other brain donors in overalls think they should inflate to the maximum number on the sidewall. Been there, done that, raised hell about it.

 

I've been perfectly satisfied with the way my car rides. It's not as silky smooth as the Rolls-Royce it replaced nor, for that matter, the Lincoln Town Cars I used to own; but it's a lot more fun to drive! I have Dunlap tires and keep them inflated to 34 PSI.

Dwayne

 

So has anyone determined what the definitive fix is? I too sense that I may have the dreaded patting issue. I noticed that my 2014 XJ Portfolio also has coil over springs in the front and only airbags in the back. Is this the case for everyone else? Could it be that this is whats causing the patting? I remember my 08 XJ8 and 04 XJ8 both had air bags all around.