hi all,

back again for some advice. been away for a while but been keeping up with the threads. great site, great threads, well hosted, great experts. keep up the good work guys.

here's my question for the experts, or anyone else thats in the know.XK8 1999 coupe 100,000 miles. i changed the front brake pads a couple of weeks ago. about a week after changing the pads i noticed the car seemed a bit noisey when driving at around 30-40mph, then it quietens down between 40-50mph, then its noisey again. i canonly describe this sound as a kind of 'rumble'. my guess is that its the front wheel bearings. also, when i removed the wheels and brake caliper, i noticed that the brake disc was not secured (normally you find one screw to secure the disc), is this how the disc is placed, without it being secured? should i suspect the wheel bearings, or is there something else i should look into first? i was going to remove the wheels again and check the caliper pistons, and maybe lubricate them, just in case they are not moving freely and causing the pads to rub the discs. anything else i should check while i got the car up on stands?

many thanks in advance for any advice.

tariq

*** still withthe elite, 'cos i got an XK8 ***

 

Mr. T,

Regards to the rest of the "A Team".

This can be a little tricky to diagnose, as the bearings can be dried out and galled enough to cause the rumble you describe without being worn enough to feel play in the bearings.

Try finding a straight stretch of smooth road, and make like you're warming up your tires for the Coca Cola 600. If the left front bearing is bad, you'll hear the rumble as you steer right. The rumble will decrease or disappear when you steer left, and resume when you're going straight. It's impossible to learn anything when both are bad, and the last time this happened to me I couldn't condemn the bearings until I had everything apart.

By the way, nothing holds the front brake disc on other than the wheel lug nuts. With the disc and caliper removed, rotate the hub and feel for roughness. You might even hear the ball bearings clacking around a bit, which is how I found the faulty ones that had no play. They were bone dry, but hadn't hadn't yet worn very much.

 

Tires are often a source of road noise similar to what you describe. One majordifference, however, is that tire noise volume is usually constant and correlated to road speed; and not intermitent. Also tires that were silent went new maybe become noiser as they wear. So you might think that your tires couldn't possibly be the source, when in fact they could be the culprit here.

Most likely it is the bearings, however, don't overlook your tires should the bearings prove to be servicable, and/or you replace them and the noise continues. gordo

 

thanks for your prompt reply guys.

i personally suspect the wheel bearings, maybe its just coincidence that the noise started soon after i changed the brakes pads.

i'll do the checks that JTO recommends, hopefully next weekend. in the meantime, if i do need to replace the wheel bearings, could you offer any tips/advice on changing them, or any links to photo's or guides to changing them. do these cars have 'inner' and 'outer' bearings, and which should i suspect first if they have both?

thanks

T

 

Hey Mr. T,

If '99 is like the '97, front bearings are one sealed unit pressed into the hub. Bearings are $65 a piece and labor usually runs around $175 per tire.

Removetire, brakes, caliper, rotor, and hub. Hub has goofy looking lock nut that is removed from the backside and bearing is pressed out and new one pressed in.

Have fun,

Marv

**The bearingwill have a very thin rubber gasket (noise reducer ?) when they come from the factory. If not , they had been changed before. **

 

thanks 97xkay8.

will look into it and post outcome for the benefit of other users of this forum.

 

been a while, didnt realise i hadnt posted the outcome so here it is.....

it turned out to be the right side wheel bearing. it was easier for me to replace the complete hub then to find someone to press out and press in a new bearings. also, the cost of new bearings and the labour to press out/in the bearings was going to be more then treble of the secondhand hub. picked up a secondhand hub from a low mileage car from a breakers yard for £75 (you may wish to convert that into your local currency). car had been seized by customs with instructions to break only! shame really because it looked like a very nice example, but it had been in the hands of a drugs dealer hence it being seized for breaking!

by the way, when fitting the replacement,i needed to cut a very small 'notch' in the backing plate. cant remember but i thinkmine was the later hub and replacement was an earlier hub, hence the notch had to be cut the allow the hub to fit.

hope this helps anyone who has similar problem.

tariq

***still with the elite 'cos i got an XK8***

 

hi joe,

the bearings themselves are about£60 per side plus a couple of quid for the 'o-rings'. you'll have to find someone to press out/in your bearings since these are pressed in/out on a hydraulic machine. but sometimes the bearings can be really stuck and refuse to come out. my mechanic showed me his press machine that had the bars bent when one set of bearings refused to come out! with regards to labour costs, you should be looking at approx 1.5-2 hours labour for both sides. in financial terms that approx £150 for labour plus parts. by the way, these prices are from my local mechanic and not the main ***********! you might want to convert the prices into your local currency.

with regards to your brake pads, depends how your car has been driven in the past, fast and hard driving will wear the pads quicker as does city driving. if you are hearing a 'screeching' noise, then it might just be dust causing it, this can be remedied by taking the pads out and greasing the rear of the pads. but if your hearing a kind of 'metal-to-metal' grinding noise, then its probably the 'wear indicator' rubbing against your disc, which means you MUST immediately get your pads changed since you wont get much more driving out of it before the pads go down to the bone, and should this happen,this WILL damage your discs! if it helps, the pads are about £65 and labour no more then 1 hour (about £50). again, local prices and not main *********** prices. not sure if pads are different for an XK8 to the XKR.

hope this helps

tariq

***still with the elite 'cos i got an XK8***

 

Got a quote from a local Jaguar dealer (in North Carolina, USA) who said it would be $610(US) to change the front wheel bearings. I've done these on other cars before, so provided it's not too much of a PITA to get the old ones out, I'm thinking of giving it a go myself.

Anybody got some photos from doing this job?

 

I did mine using a shop to press them out and in. The hardest part was getting the ball joints out. But I bought a $30 scissor-type press and they popped right out.

If you get the hub off, any shop would remove and replace them for a few bucks... certainly less than $600.

 

mmmm ... would that be a pickle fork perhaps? Mabe I should consider just DIY here too. I have a 50 ton shop press .. I've read that 20 tons is more than adequate. If I DIY I'll try to remmember to take some pics. Just got my Cat two days ago .. but I suspect that at 75k I may have a similar noise source. the bearing for a 2003 xk8 is a Timken 510010 .. or equivalent .. $29.63 ea. at hubbearing ... not an endorsement, except for the Timken brand part.

 

Hey attaboy, lots of potential causes for 'noises' in the suspension, gordo is one of only a handfull of xk8 owner that I have read needing to replace wheel bearings. My 03 has 108k on it, and I've done everything just about...except bearings.

Upper mounts, lower shock bushings, upper and lower control arm bushings, and sway bar bushings (this was the noisest SOB!!)

sounds like you know your way around the mechanical end of an car, so I'm sure you'll enjoy part swapping!

 

Well I know they are supossedly lifetime-sealed .. like the 4.2's are lifetime valve adjusted .. gotta getr' off the ground and do the 12-6 shake-wiggle test. She has BF Goodrich T/A's on ... I have see ZIP for those mentioned anywhere pro or con, but it could simply be tires and alignment. Alignment is first order of business.

She is absolutely rock-solid in the suspension category .. I hear nothing knocking or rattling, both on my own road ravaged by winter, or on paved roads straight line or coca-cola. It is definetely associated with wheel rotation .. barely audible from mabe 30mph and up, but this Cat is sooo quiet .. any road "whiring" is noticable, to me anyway. My ex lives next door .. she says she can't hear anything, but says she feels vibration in the steering wheel. As above .. an alignment will verify or negate possible sources .. perhaps for both observed phenominae.

Well .. I used to love to swap motors .. trannys .. all that stuff ... about 40 years ago .. LOL. I used to be able to lift and place a T98-R granny tranny on my chest .. nice how it works out, that I have no interest in doing what I am no longer capable of .. LOL.

This is the first "car" I have purchased since 1970 .. a new Toyota Corolla with optional AM radio for $2,068. Trucks and work .. lotta years. This XK8 is sooooo sweet. While the Apollo wiring diagrams pale in comparrison, this bb is an incredible resource. I have 8 tractors here, so "wrenching" on stuff is not optional .. the Jag is my reward.

 

For the record I did not need bearings. They were replaced as a preventive measure. It seemed like a good idea to swap out the bearings while I had the suspension apart trying to fix a front end shimmy problem.

I believe early model XK8's have smaller bearings; a problem which was corrected in the first major upgrade around MY 1999.

 

Thanks for clarification Gordo, that leaves one less who actually 'needed' them.

 

I wonder if the toasted shock moutns add any additional stress to the wheel bearings? I can't imagine such a heavy camber, with the jarring of steel on steel,not doing at least something to them....