I've been really enjoying my 2009 XF Supercharged for the week I've had it so far. About 150 miles driven on it between the "polar vortex" snowfalls we've had here. I'm approaching the end of the time I can return the car to the dealer if I don't like it, and I wanted to "double check" that the ride quality I'm experiencing is "normal".

Understand I'm coming from a Mercedes perspective. The car traded for the XF was my S600 with the long wheel base, 275/40-18 tires, and active hydraulic (ABC) suspension system. It's obviously in a different class than my XF, however it was my daily driver and is my last point of reference. It's suspension was what I would call firm and supple ("sport mode"), with absolutely no body roll on turns, and would glide smoothly (but no float) down the highway, over railroad tracks you couldn't feel a thing, and it zipped around town with ease.

I'm finding the suspension setup on my XF *REALLY* harsh by comparison. I feel EVERY bump, and going down the some parts of the highway, it follows every contour of the road with the corresponding "rebound" that goes with it. Even my wife commented on it. One section of freeway has slight dips between expansion joints for several miles, and I was bouncing up and down to the point I could not accurately push the touchscreen controls because my finger kept missing the button. It also LEANS much more on turns and on/off ramps. That being said, the XF is much more nimble and responsive to steering commands. And let me be clear, the ride is not so harsh as to be teeth rattling. It's just really different from what I'm used to and I'm having a hard time not only adjusting, but imagining a long distance trip in it.

So my question: Is this hard ride quality normal or is there something wrong? It has the 20" rims and low profile tires, which I imagine is contributing to it. Just to be sure, I had my indy mechanic put it on a lift just to double check things. There are no errors or codes. All the bushings/joints are in good shape, and all the struts are green in color (I don't know if that's stock or aftermarket??).

I was told the '09 XF S/C has the CATS suspension. I thought the CATS suspension was more "active" and would have smoothed things out when being leisurely, but perhaps I'm expecting too much from it. Is there a button or menu option somewhere to adjust the suspension settings? Maybe it's not getting softer when it is supposed to?
If this is "normal", I can deal with it and I can adjust my expectations of it accordingly. It is fun to drive (I can imagine taking this to the track and having a blast) and please be crystal clear I am no means saying one vehicle is better than another. I know they are different. I just wanted to be sure what I am experiencing isn't some crazy aftermarket setup from the prior owner (I've never seen green struts before).

Thanks for helping me put it all in perspective.

I would check tire pressures first. 20's with low sidewalls and too much air won't be fun at all. Also, what transmission setting were you in? If you weren't already, try it in Drive, not Sport and see if it isn't a little better. Not sure if the 09 had the dynamic mode, but try it in the off position as well. I wish I knew if the suspension should be green. Maybe ask Brutal as he's a Jag tech?

Thanks for the quick response. Tire pressure is 32 psi front and 35psi rear (cold) all around. Trans setting in "D" (not "S"port). Haven't messed with the dynamic (checker flag?) button or the DSC button yet as the roads have been snowy/slick and I'm not familiar with the car enough yet to experiment. I did try the snow button, but did not notice any noticeable difference except the 2nd gear start from a stop.

That is exactly my pet complaints against some late Jaguar models. I do have and XF with 18" wheels and, yes, the ride is stiff and given the "wrong" type pavement, could be called harsh. Still, not as harsh or bad as the ride of my '12 XJL, which I call terrible. Of course, given that you have 20" wheels and likely even stiffer springs, I could understand your concerns.

I did voice my opinion here on the forums that the Jaguar suspension team was not up to the task as they should not have used such stiff springs for their sedans, particularly not for the limousine sized XJL. Should have gone with softer springs and thicker anti-roll bars to prevent body roll.

For me, my XF's stiffness is acceptable, and I like its handling the most amongst the last 4 Jaguars that I have owned. It is the XJL that is unacceptable for its nervous, vibrating stiff ride that beats me and my passengers up over longer highway distances. As of now I am running only 21-22psi tire pressures in the XJL just to make the ride acceptable. Also, I have an appointment with a Jaguar of NA engineer next week to see what can be done with the ride on the XJL. It is a fairly widely covered issue that the Jag cust. service agent confirmed.

Albert

Tanman,


I currently own a 2012 XF. Before I made the purchase I test drove a Mercedes Benz E550, 09 XF SC and another 2010 XF.


E550 had the most comfortable ride out all of them. It absorbed imperfections much better. It glided over everything. I believe it only had 18" wheels on it, which helped. That didn't stop me purchasing my XF, as feels like a sports car compared to the E550.

The 09 XF SC had the hardest ride out of all the XFs due to it's large 20" wheels. So, what you are experiencing is normal. The rear wheels are 9.5" wide, that's part of the reason why it follows the contours on the road.

What I would recommend is perhaps buying another set of OEM wheels in size 19". It will make a huge difference in the ride quality, but still have the responsiveness we love these cars for.

I should add that when I switched wheels and tires between my XJL and XF the XF rode beautifully on the XJL's 19" wheel/tire combo with 245/275 Hankook Ventus V12 tires. The XJL HATES those tires, the XF loves them. Go figure...

Albert

Thanks guys! Based on what you are saying, my XF is performing the way it is supposed to, which is a relief of sorts. I figured the 20" wheels had a lot to do with it despite their being brilliant to look at!

I'll take a little more time behind the wheel for now and make a decision in Spring when I would consider a tire change anyway. I may get used to it or grow to appreciate it more. I can always swap cars with the wife if it get's too bothersome.

Thanks again.

Yup, low profile tires combined with overly stiff spring rates (in my opinion), makes the XF ride a bit rough over anything but the smoothest pavement. I think Jaguar should have used stiffer anti-roll bars and a lower spring rate on these cars, but who am I to say.

The 19" wheels seem to be perfect for the XF. I had them on the first and it seemed that anyone who got in the car commented on how good the ride was, most would say something along the lines that it was the best that they'd been in. It had the standard suspension setup, and I thought it drove better than XFs with 18"s that I'd had as loaners. I had 20"s (stock) on the second XF, and it was a lot harder but still pretty good. It also handled a lot better, but I think my missus preferred the ride in the first. I've got 20's on the XKR, and I think the ride in that is probably on a par with or better than the second XF.

Take it to your local Jag dealer (assuming that's not where you bought it) and have them test-drive it. It doesn't sound right to me - I have the 2010 XF SC with 20inch tyres and I haven't found the ride to be harsh. It's definitely firm, but to me that's the feeling of a sports sedan vs. an executive limo. You sound like you are describing it as terrible - and that doesn't sound right. Worth paying a couple of hundred dollars of diagnostic to make sure all is well... I test drove a 2009 SC when I was looking to buy and it seemed fine to me too.

What tyres do you have on the car? On my previous vehicle (not a Jag) which also had low profile tyres, I found the switch from one brand to another to transform the ride from totally unbearable to quite ok. As axr6 says above, different tyres perform very differently on any given car. So that could be a factor.

Of course if you can find a 19inch set of wheels that fit over the SC large brake calipers, then that would help - but I would want to be sure there wasn't an underlying issue first. Good luck!

In drive my '11 xf SC in dynamic mode as I like the ride better. It has less bounce to my mind.

I have a 2005 STR. It has the same suspension as the XF. Yes the factory CATS struts are green.

Check that there is no oil or oily film on the struts. That would indicate they are leaking. You did not post how many miles you have on the car? Now if you had 100K miles on the car I would expect a small amount of oily grime on the struts just from time and use. That is entirely normal.
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Doesn't the Merc S600 use air springs? If so then the XJ is the car for you.

The XF is the sporty Jaguar sedan so the spring and damper rates are towards the firm end of the sports luxury spectrum.

CATS only adjusts damper rebound settings. The thump you get is from the springs and not affected by the damper adjustment. Only really expensive systems are adjustable in bump ( jounce) as well as rebound (bounce). Also, the thump may giev you the impression that the ride is too firm but actually not much of that thump reaches your body in reality. It can be very hard to separate the various inputs to total N V H impressions, which is why the engineers treat them as one area of development.

CATS firms up the rebound rate of the dampers which controls the rate the springs extend back to normal after a compression of the suspension.

Basically, spring rate determines comfort and rebound rate determines smoothness.

Mercedes latest S class has anticipatory ride software which uses radar (similar to the forward adaptive cruise) to inform the suspension computer what's coming up. Did your S600 have that because if so nobody can beat that at the moment for comfort.

Tire brand/compound has a tremendous affect as well. I drove a XF with Michelin Pilot Super Sports and the grip was phenomenal but the ride was harsh and very loud. The XF I bought has Continental DWS and it is a much better ride and sound.

Thanks again for the responses. I've got 55k (miles) on the car. I looked under the car when I had the tires rotated (Conti Extreme DWS), and the shocks are dryand clean on all four corners, which I'm very happy about.

Thanks for confirmation of the CATS components being GREEN and the explaination of how it worked with regards to rebound, dampers, and spring rate. Makes a lot more sense to me now that CATS is more semi-active and has more limitations than the S600.

To answer your question, the S600 is not the "airmatic" used in a lot of Mercedes vehicls (including some S500/550), but instead uses a hyrdaulic ram (Active Body Control - ABC) at each corner to constantly change the pitch, roll, yaw of the car including when cornering to "lean" the car to keep it perfectly level.

To illustrate, this is a link to a video of my vehicle hooked up to my XENTRY/DAS multiplexer (chinese clone) performing a "rodeo" to purge the lines after I did a hydraulic fluid change. As you can see it does a lot more than just affect the spring and rebound rate. It can literally lift the car up to 4 inches at any given corner, or a tire completely off the ground. This is how such a large sedan can pull a .89 skidpad with the proper tires.
https://www.facebook.com/photo.php?v...75931683619407

How do you rotate the tyres on an XF SC? Doesn't the 2009 have the staggered setup with 8.5inch wide at front and 9.5inch wide at rear? Or do you have an aftermarket wheel setup?

Yes, staggered. I had them swap side to side; the Contis are asymmetrical but not directional. Force of habit. The benzes rwd camber is so aggressive it tended to chew up the inside tread. It also had an electronic diff not LSD, so the one side tended to get eaten up faster than the other. I'm hoping the XFs setup is a little easier on them, but I'm under the understanding it has an electronic and not a LSD as well.