XF Rear Suspension

[WULLIE4567]

Hi All
Not much in hear about XF suspension, so maybe this will get things started. I have two Jags to play with first one is a 2000my XK8 4.0ltr owned for 8yrs, next the main car is a 2009 XF 3.0 ltr diesel 68500 miles owned for 3 months bought from Main Jag agent with a years warranty.
Within a week of owning it I noticed a heavy clunking from the rear both sides, I returned the car for inspection and both rear upper arm bushes are shot along with the rear shocker bushes. The car is booked in for both arms and lower shocker bushes end of this week. + a new window regulator d/s/f it was stiff and would not stay up even trying silicon spray in rubbers.
Apart from that we love the car, we tow a big caravan with it no prob's. I'll follow this post up with another let you all know the outcome.

Wullie.

[WULLIE4567]

Hi
Update on clunking, The Jag agent fitted two new rear upper suspension arms + new door regulator, the window now works a treat but the clunking is still there, the shocker bushes haven't been done? I was back shift so will have to deal with it Monday . dout they never road tested it or maybe the mechanic is deaf.
Has anyone had this noise before it's mainly when shifting the body wait from side to side like when going through roundabouts & cornering on 'A' roads.
I was going to put it up on my ramps today have a good check at the antiroll bar bushes etc but the heavens have opened. Any help would be appreciated.

Wullie

[J44EAG]

S-type experience only but XF is similar.

Click-clack is usually arb to wishbone vertical links. About £32 a pair on ebay. Life can be as low as 60k miles.

Bonk-thonk on speed bumps or potholes is arb bushes. Materials now better than when the first S-types came out. Poly prop replacement upgrades from SNG Barrett for the same price as standard squashy types or on ebay.

Knocking is usually damper bushes. Damper failure at your mileage would be unusual. nasty little job changing bushes on dampers. Might be more economic in the long term to consider damper replacement. If I were towing, I would replace and upgrade to gas sport 30% B6 Bilstein units. Cost for a pair of S-type units from Larkspeed (one of the few uk suppliers and the cheapest) is £360 with VAT and delivery. Well worth a few pounds extra. Firmer but not harsh.

You have had lower rear wishbones done so that should be out of the equation. What condition are the upper rear wishbone bushes?

Mike K

[oldtimer]

Mike,
I can't see in the text where the lower bushes have been attended too! Would you care to comment.

Although I have never had the opportunity to inspect an XF on a lift, from what I have seen I reckon an XF is an S type with a new overcoat

P

[J44EAG]

Yip, going daft!

Uppers have been do I see, so perhaps the lower rears need some investigation. They can make noise when worn.

Thanks for the heads up, Phil.

Mike

[WULLIE4567]

Mike/Phil

Thanks for your input Mike, I will get it up on my wee ramps & check all bushes & drop links myself before taking it back to the stealers who don't seem to be too clever (already had dealings with them). When driving the car to Glasgow last night (full tank) I noticed when braking & coming to a stop sharply eg' lights the clunk is there, also when taking off from a stand still clunk, wasn't doing that before they fitted upper wishbones . I was looking around other Jag forums & found a posting with same problem, it turned out the fuel tank was slipping back and forth & side to side apparently a problem with some XF's ? this might fit in with what I herd last night. Fuel is very heavy as we all know, this will be another thing to check.
I will post my finding & hopefully get to the bottom this .

Wullie.

[raysearles]

you have probably solved it by now, but the thump thump noise from rear suspension was one of the items covered in the XF seminar, its a known problem with the bushes as Mike has already surmised, and as such I would have thought if the car came from a main dealer they should know about it and be prepared to put it right under warranty.

[WULLIE4567]

Ray
Thanks for your reply, The car is booked in on Tues coming they now reckon its the front shocker or top mount?? . so we will see. I will keep you all updated with the results of that. They paid for the rear upper arms and they will be paying for the front end.

cheers
Wullie

[WULLIE4567]

Well got car back today after many days in workshop, they have fitted new n/s/f shocker & top plate new, still making noise from n/s/f crack clunk 'o' dear, they then fitted 13 new parts from a new car ( so I'm told) and still making noise. Now they have sent noise recording to jaguar boffin's see what they think. Thank goodness am not paying for it I hope. I love the car but this is just p---ing me off, think I'll buy a skoda.

Wullie

[raysearles]

Are they sure it is suspension noise and not "fuel slap" - the XF has a notoriously noisy fuel tank to the extent that Jaguar fitted some plastic baffling to cut it down - as your dealing with a main dealer I suppose that's a stupid question because they ought to know that sort of stuff - hope you get it sorted soon

Ray

[oldtimer]

Have read the thread, nobody seems to have homed in on the rear lower bushes. Need some big levers for that.

Don't pull the car down on yourself + all the rest of the safety stuff

[J44EAG]

I wrote an illustrated article in the magazine about rear lower wishbone bush issues some years ago. The parts are identical for S-type, XF and X350 which all use similar bush components. Yes, they do clank if worn.

The bushes fitted to two of the three registers in lower rear arms are a patented "spherical" type. The bushes look similar to void bushes but that is where the likeness stops.

The bush is fitted with a tube which has a ball approximately half way along the tube. The bush is designed to allow rotational movement and a degree of radial or conical movement required when rear tracking is adjusted. The tube and ball sit in a nylon type antifriction cup which can wear after a prolonged period of use. Here is one I cut in half earlier.......Note the cracks in the nylon running surface.

Typical life span of a bush is around 80-100k miles. The bush is sealed and no adjustment is possible. It forms an almost solid bush when in good condition. When worn, the nylon cup breaks up and wear is noticeable when levering the wishbone with a pry bar. Little force is required when levering. If the wishbone doesn`t move within the sub=frame bracket or hub carrier mount, then it is fine. If movement can be seen, then the bush is shot.

The lower wishbones, N/S and O/S are Y - shaped. The bush located behind the car sill is a rubber Metalastic type and failure is almost unheard of. The two other bushes are located, one at the lower joint, wishbone to lower hub carrier and the other in a sub-frame bracket towards the area of the diff drive pinion.

Contrary to what a Main Dealer will tell you, these bushes ARE available but NOT via the Jaguar parts network. These bushes are available from Racing Green Cars, Winspeed or North East Jaguar Spares. Prices are around £40 each.

For years we were had over a barrel if a bush failed. We were obliged to buy complete new wishbones if bushes failed. Costs were about £500 per individual wishbone. Jaguar maintained that it was dangerous to consider bush changing as it could be possible to crack the slender aluminium wishbone castings and the issue become dangerous. Yes, you could break a casting if you were clumsy but if that were to happen you would go and buy another second hand unit and have another go! Jaguar were not best pleased when bushes became available on the after market....They were perhaps even less pleased when trade sources also started selling genuine manufactured parts at around half the cost. That situation still exists today.

Now, several years on, many independent garages change bushes as a standard service and have saved customers hundreds of pounds. Provided one is careful with fitting techniques there isn`t an issue. Indeed, the job of bush changing is not that difficult once the wishbone is off the car. Given a bench press or even just universal bush change mandrel set (about £100 on ebay) the job is in my opinion relatively easy for a man with a reasonable engineering experience and background. I`ve changed a couple of bushes recently using both bench press and mandrel set. If any one method is prefered, I think it is using the mandrel set and threaded ball raced pull units. That makes it a very controllable process. Pull the old units out having taken precise measurements between centres, then pull a new bush into the wishbone. Stop and evaluate if a jam up is felt.

If a bush has worn, you have the above options for direct replacement or repair. If you elect to repair a wishbone by fitting new bushes, you will have to come outside the Main Dealer network for that to occur.

More waffle on the subject here. Just one post on the subject from the S-type BB.
http://www.jec.org.uk/forums/viewtopic.php?f=200&t=4834

So that rear lower wishbone bushes discussed yet again. Hope this helps.

Mike

[oldtimer]

Well done Mike, yet again

[WULLIE4567]

Thanks a lot for that Mike great post will help more people than me I would think, I will examine the bushes talked about in your post. The car is still clunk/cracking away more noticeable going round roundabouts & when cornering on 'A' roads, also when I reverse into my drive before the wheels hit the low kerb sometime 2 or 3 cracks, seems to be when the body weight shifts defiantly the front. When my daughters with me she says there's a clunk noise from the rear as well? as you know they have changed the rear upper wishbones.
I just feel the main dealer don't know what there doing, maybe I should get an independent Jag garage to look it over.

cheers
Wullie.

[J44EAG]

A second opinion may well help. Take to a good independent operator.

As I said earlier, click, clack from either end is usually the arb to lower wishbone Z links. Life span is about 60k miles for those links. Bonk-thonk is arb to chassis rubbers.

The new type front lower wishbone banana arm bushings can also cause issues but that tends to show as car wander rather than noise. Lemforder produce replacement bushes for those items. Loads on ebay.

Also worth levering all wishbone ball joints. Early S-types tend to suffer with premature wear in the front lower joints although later cars, XF and X350 models had this problem by and large designed out. The ball joint in those cars is inverted and forms part of the banana arm arrangement rather than being fitted to the vertical leg/wheel hub/ ball joint unit on the early S-types.

Some more food for thought. Are all nuts and bolts within the suspension tight, including wheel nuts?

Are all damper top mounts good?

Are all damper bush to wishbone bolts tight?

Have all four arb to wishbone links been checked?

Have all four damper spring pans been checked for correct spring location or entrapment of stones or other debris?

Have all four damper top mounts been checked for top mount nut tightness?

Are there any damper leaks visible?

Can you emulate the click by bouncing the car on its suspension?

Hope that helps.

Mike