Intermittent rear wheel or driveline vibration

[BrianG]

Andy,
Thanks for the reply. I don't think there's a noticeable rumbling noise (but it may be masked by general road noise from the low profile tyres). I've been living with this problem for about 20K miles now and the noise seems much the same; the vibration is getting worse though.

Like you, I won't be attempting this myself. I'll shall be looking for an independent rather than the main dealer, but I may have to request they just change it rather than ask "do you think it's faulty?" (see previous reply to Mike about the front wheel bearing being 'no fault found'.)

Brian

[andypryce]

Good luck Brian. The fact that it hasn't changed over 20k miles would I guess point against a bearing, as I think once they start to fail they get worse quite quickly? Could be wrong though ..

[J44EAG]

Doing it in the sun when the sciatic isn`t playing me up is just about tolerable! if it is, then stay clear when i`m on the job!! !`m usually in a terrible mood!!!

Front wheel bearings can get a very gravelly feel about them from about 79k miles and they "wow". Take the front brake pads out and spin the hubs. A good one will be silent. a worn one can sound like a cement mixer eating a bag of peanuts and make a very dry noise. To replace, remove the four bolts on the rear face of the vertical hub carrier. Two are T55 Torx and two are from memory 17mm hex conventional. With those four bolts removed and the aBS sensor removed, give the hub a couple or three good clumps with a lump hammer. You may be lucky and the bearing cartridge will fall out on the floor. Thats very rare though.

If the bearing does not drop out of the carrier leg, then it will have to come out of the car in the leg. Anything up to 5.5 tons pressure may needed to be applied via a bench press. Around 3 tons pressure is the norm.The steel cartridge and ali leg can corrode together due to mixed metal galvanic action. Removal can be brute force times the square root of ignorance. Once the bearing is out, clean up the leg and fit a new bearing with Duralac anti-corrosion paste and refit the bolts. rubber gloves when using the paste. It has barium in it which might cause your hair or other bodily parts to drop off if you don`t protect yourself correctly. Use decent replacement bearings can be had on ebay for around £70 each to OE spec. I paid just £126 for a pair recently.


Here is all about S-type suspension work in a very long thread. The X350 and XF are almost the same with some variances a as regards the lower front wishbone revamp.
http://www.jec.org.uk/forums/viewtopic.php?f=200&t=8040
If one bearing is near finished, then the other side will be not far behind it. Best to change as a pair. Done loads of these over the years.

Mike

[xj40s]

Don't know if you ever got this sorted. Similar problem on a 1994 3.2 XJ40 was caused by the characteristics of the jurid coupling at the diff or its effect on propshaft alignment.
The x350 manual (DVD) has a very long section on noise, vibration & harshness (NVH). I do not know if vibration analysis equipment is available to buy or hire at reasonable cost. With vibration analysis equipment the problem area can usually be found very quickly.
PICO do an NVH diagnostics kit at about £600 to £800. If you contact PICO they may be able to tell you of a garage near you that has the kit.

PS I know this is an old topic, just posting for future reference

[BrianG]

Thanks for your post, I will bear this in mind for possible further action (the Jaguar main dealer who investigated all the usual causes was supposed to have the special NVH kit but was very reluctant to use it when I asked). I still have the problem, although when it does occur it is markedly reduced from when I first posted. I put this down to getting all the wheels "road force balanced" (or more correctly 'radial force variation' balanced). This was done at Harwoods Jaguar, Chichester, who are one of the few places in the south east listed as having the special machine for this task, which is made by Hunters. Recently I have noticed that the left rear brake disc makes a noise, when applied at high speed, which is very similar to the noise and vibration I was getting originally. The discs looks well worn and may be warped, so perhaps it will solve the problem completely when I replace them in the near future.

[J44EAG]

Discs when worn can certainly warp and loose weight as they get used. My front discs each lost 0.75Kg when compared to new discs. Fitting new discs rid the car of cruising vibs and brake wobble. Fitting new wheel bearings also helped. Wear all adds up and when you get multiple issues together, you suddenly find parts of the car need a rebuild. Been there, done that with my XJR.

With eighty thousand miles recorded last year, I found cause to change every bush on the car with the exception of the anti-roll bar bushes, discs and pads, wheel bearings, tyres, balance and tracking. Then the car became much more usable and pleasant to drive.

Mike.

[Denisxj]

Hi Brain did you ever get this problem resolved as i'm having the same problem with my X350 and can't find out what it is many thanks Denis

[BrianG]

Hi Denis,
Yes and No! The biggest improvement came from getting a four wheel alignment as close as possible to spec and then all four wheels 'radial (or road) force variation balanced' at the one Jaguar dealer in the south that has the right machine, Harwoods Chichester branch. (Some better tyre firms also have this kit: Google for ' location of Hunter GSP9700 machine ') This has meant that the car hardly ever gets the vibration and is OK most times up to over 90 (ahem) , so mostly good enough.

However I have recently noticed that at speed similar to where the vibration would start, when the brakes are applied firmly the rear left brake now makes that corner of the car have an almost identical growling/rumbling noise. The rear discs (now at 100,000 miles) and are due for replacement soon; I suspect that the left one in particular as well as being quite badly scored is also warped, hence a possible cause of vibration. It will be interesting to see if new discs finally eradicates the problem.

Good Luck with your own problem!

[J44EAG]

As per my previous posts on the subject, old worn discs can loose a lot of weight and perhaps not always uniformly or evenly. When I changed all for on my 350R recently, there were improvements at every stage of the game. Subsiquent rebalancing using an almost new machine at Tyremark in Caterham, rid the car of vibration at any speed and also whilst braking.

When the car has been sorted, it becomes quickly evident. A completely different drive results. With the 20" rims and tyres, I`ve found it not uncommon to have wheels rebalanced on an almost annual basis dependent on driving style and mileage covered. Not unexpectedly, the near side front tyre is the one that suffers most and usually through fast roundabout cornering. It doesn`t take much to mess up the wheel balancing when the car is used in this fashion.

Mike

[oldtimer]

Hi Brian G,
I hardly dare ad to this thread as Mike K will be along to say I am bleating on again. 'ole fellows of a certain age are permitted one or two phobias. One of my many is in connection with brake discs.

It is crucially important to ensure that the hub, brake disc mounting face is cleaned to appear as new. Also that the disc mounting face is absolutely spotless. It should be a matter of routine to fit the disc and carry out a disc run out check using a DTI (dial test indicator) The industry standard tolerance is Zero to 40 micron (1.7 thou) of run out which is achievable. Failure to achieve this runs the risk of brake judder and vibrations after about three months depending on vehicle usage.

I was required to visit Dealers in connection with Customer complaints and I could write a book about what was found.

Tyre depot Gorillas with their windy guns even managed to distort hub mounting faces and so the story goes on.

You could ask to see the hub faces prior to the discs being fitted and then the DTI readings for each disc. That could be interesting

Having made discreet enquiries down the years, most places don't even consider doing a run out check but the times for jobs book which is the basis on which your labour time is based calls for a run out check ,so you are paying for it anyway.

So when the customer complains of brake judder it has to be those crap discs have distorted or warped. Nobody ever holds their hand up to say they did a crap fitting job.

Well I won't bleat on any more but perhaps something to think about