SOS - Tyre Nightmare - Please Help

[anonymous-user]

All this swapping between summer and winter tyres is more trouble than it's worth it would seem.

[cambiker71]

Have they left a spigot/adaptor out?

[utterly83]

Faxo said:

Is it through the steering wheel, or full car?

At work (Audi), Q3s have a problem with vibration, and it's the front arm rear bushes

Also, it's been lifted - trying to think of something that would've moved/been disturbed when lifted

The only thing I can think of is a driveshaft - if it's through the wheel, then this can be discounted. However, it's its through the car, I'd maybe start to question the rear driveshafts - it'd have to be a massive coincidence, but stranger things have happened

Good thinking, thanks. It is through the whole car, not the steering wheel. It was on a lift, rather than jacks. I think I will check the driveshafts for run out, any idea what the runout should be on a drive shaft?

[Faxo]

rallycross said:

it wont be a drive shaft on a low milege bmw.
I had a wierd wheel wobble only when warm on an audi TT quattro, which was a front drive shaft / cv joint failing, so it needed 10 minutes drive to get hot enough to cause the vibration which was so severve you could only crawl along at 20 mph once it started. A bmw would not be able to do that. Still think its a bent / damaged wheel, if its a wonky tyre you should be able to eliminate it by swapping fronts to rears as the rear disguises a damaged tyre/tyre bulge relative to when its fitted on the front.

Why not, do faults only happen on high mileage BMWs?

Re a buckled wheel - if they've been off and on, and checked and checked again, by more than one outlet, SURELY one of the times someone would notice this. Also, why would a buckled wheel only happen when warm? It's still buckled when cold.

Re runout, I don't think it'll be an issue such as that, it's as if it's dropped a ball or something. Obv when it's lifted, the suspension drops to its stops, and so pulls on the CV joints - perfectly normal. However, IMO, that's where something happened. I'd be tempted to bite the bullet and take a trip to BMW, or a specialist who knows what they're doing. As with any problem, you can throw money at it with alignments and balancing etc, but a half hr diagnostic could pin point the issue

[utterly83]

Its done 77k miles.
I will try swapping wheels front to back. Very frustrating. I cant see a diagnostic helping, its unlikely to be anything electrical i think.

[rallycross]

Faxo said:

Why not, do faults only happen on high mileage BMWs?

No a BMW even with a knackered D/S will not cause a vibration through the car, its something else wheel or tyre related.

[utterly83]

cheers all. will report back.

[TimLambert7]

I have only flicked through the thread so it may have been mentioned already, but..

I had something quite like this and it turned out to be a sticking calliper. It was diagnosed by going for a drive and feeling the temperature of each rim, the offending wheels rim was vastly hotter than the others.

I had serious wobbling between certain speeds and very little either side of it.

[utterly83]

TimLambert7 said:

I have only flicked through the thread so it may have been mentioned already, but..

I had something quite like this and it turned out to be a sticking calliper. It was diagnosed by going for a drive and feeling the temperature of each rim, the offending wheels rim was vastly hotter than the others.

I had serious wobbling between certain speeds and very little either side of it.

Tim you nailed it..

OK, so... feeling daft but I lifted the car and one of the rear wheels barely spun... I have a binding brake disc/pad. Now I look again, the disc is blue... from over heating on the motorway. This makes perfect sense.
The disc and pads are badly worn anyway, but I don't want to replace them with brand new items and then have this reoccur...

Why would the pad bind to the disc? I assume some remedial work is needed like rebuilding the caliper or bleeding the system or something?

[danjama]

No idea on the build of the calipers on your car, but on my mr2 the calipers seize because the rubber boots that protect the sliding pins deteriorate, and of course the pins dry up and stick.

[Megaflow]

utterly83 said:

TimLambert7 said:

I have only flicked through the thread so it may have been mentioned already, but..

I had something quite like this and it turned out to be a sticking calliper. It was diagnosed by going for a drive and feeling the temperature of each rim, the offending wheels rim was vastly hotter than the others.

I had serious wobbling between certain speeds and very little either side of it.

Tim you nailed it..

OK, so... feeling daft but I lifted the car and one of the rear wheels barely spun... I have a binding brake disc/pad. Now I look again, the disc is blue... from over heating on the motorway. This makes perfect sense.
The disc and pads are badly worn anyway, but I don't want to replace them with brand new items and then have this reoccur...

Why would the pad bind to the disc? I assume some remedial work is needed like rebuilding the caliper or bleeding the system or something?

Ah, yes. That happened to my wife's S2000. Forgot about that, I was chasing wheel balance, etc as well before the seized caliper was found.

New caliper, discs and pads required.

[tonyvid]

At least you have found the trouble. I had a horrid vibration when on a light throttle that got much worse when lifting off or coasting - after changing all sorts of bushes, swapping tyres etc it was a drive shaft.

utterly83 said:

the disc is blue... from over heating on the motorway. This makes perfect sense.

You might want to get your nose serviced as well

[Mr2Mike]

utterly83 said:

Tim you nailed it..

I did suggest this over a week ago

[Devil2575]

utterly83 said:

TimLambert7 said:

I have only flicked through the thread so it may have been mentioned already, but..

I had something quite like this and it turned out to be a sticking calliper. It was diagnosed by going for a drive and feeling the temperature of each rim, the offending wheels rim was vastly hotter than the others.

I had serious wobbling between certain speeds and very little either side of it.

Tim you nailed it..

OK, so... feeling daft but I lifted the car and one of the rear wheels barely spun... I have a binding brake disc/pad. Now I look again, the disc is blue... from over heating on the motorway. This makes perfect sense.
The disc and pads are badly worn anyway, but I don't want to replace them with brand new items and then have this reoccur...

Why would the pad bind to the disc? I assume some remedial work is needed like rebuilding the caliper or bleeding the system or something?

And the moral of the story is don't just assume that a new problem must be related to the last time the car was worked on

You need to strip the brakes down and find out what the problem is.

[utterly83]

So I replaced the discs and pads, and cleaned and lubricated the caliper’s slide pins and pad contact areas which were filthy. I peeled back the rubber boot surrounding the piston but it was immaculate under there so didn’t touch it. I reassembled everything and the caliper is still dragging and I warped another disc.
Does anyone have a comprehensive caliper rebuild guide or should I save the leg work and shell out the £90 quid for a new caliper?
Seems a shame as calipers are so simple

[Megaflow]

I wouldn't bother trying to rebuild it, to do the job properly you'll need a full seal kit and a new piston. It is a fiddly job and everything needs to be spotlessly clean. I'd buy one that has been professionally refurbished.

[BritishRacinGrin]

27th March

Mr2Mike said:

A binding brake can cause vibration after it's heated everything up - the wheel change might be coincidental. Have a feel of the wheels after a high speed drive and see if one is noticeably warmer than the rest.

BritishRacinGrin said:

Sounds like it's brakes or a worn suspension bush for me. In my opinion, the fact the fault is intermittent rules out anything wheel / tyre related.