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LewisM
28-02-2013, 11:58 PM
OK, back to car issues. My 2003 VW Passat (2.3 L V5, auto) now has in excess of 250,000 on 95% original components, and of course, things are starting to go - brake pads and rotors replaced, bearings...

Will need a shock absorber refit soon, but need to sort another issue first. A weird noise.

When I had the brakes and rotors fitted last week, I also got new tyres. INSTANTLY when driving on them, there was LOUD road noise. Took them back, and they said they will wear in etc. I knew this, but still demanded a wheel alignment and total balance, as there was definite shimmer (though not really FELT, just HEARD) sounds when driving, especially on smooth roads (not the old coarse gravel bitumen roads)

Well, it's getting weirder. The shimmer SOUND (note - MINIMAL vibration) will usually only begin after about 20 minutes driving - long enough for things to get warm. And the SOUND is only really noticeable on SMOOTH bitumen. As I said, it SOUNDS like a wheel shimmy, but without the vibration, nad it also SOUNDS like an out-of-round tyre(s), again, without vibration (well, much anyway). The sound will almost disappear at 100km/h, and then reappear between 80 and 40. At lower speeds, it is exclusively a lub-lub sound like an out of round tyre.

Some thought came to mind:
1. torque converter
2. U joints
3. out of round tyres.

Now, the car goes into gear perfectly. It accelerates perfectly. It changes gear flawlessly. It makes no abnormal noises when stationary, and there is no engine fluctuations. I think this rules out the TC.

U joints - I haven't gotten RIGHT under yet to have a play with the driveshafts or check for play as yet, but I have my hunches on it being the U joints. At low speeds, I get a chirp sound from the driver side area, and also sometimes a little clicking when turning (though different to a bad CV)

Tyres - I also haven't had the new front tyres rotated to the back to see if it alleviates the issue as yet, but the lub-lub sound makes me think PERHAPS these cheap Chinese "Bluestreak" tyres may be at fault, at least partially, coupled with the U joints.

I HAVE had Pedders do a 28 pint check, and they did claim a leaking left gas strut (it's actually NOT - it passes all "bounce" tests etc very well. The tie rod ends etc all passed. They said the rear struts were "soft" (all Passats actually ARE!) - and these struts ARE 100% original from manufacture. The also said the rear ball joint seals were perishing, but IMHO that won't cause the front end sounds I hear. The car makes NO odd noises going over bumps etc.

So, thoughts? U joints? Not TOO expensive doing them if need be (or a complete refurb drive shaft is $504 per side, VW factory recondition) Maybe an out of balance drive shaft caused by worn centre bearing or?

I want to keep the car a bit longer, as I love the car (been together 5 years now). I replaced the radiator overflow tank today, as that had a crack in the steam vent pipe, and it was spraying coolant all over the injector solenoids, port change over valves etc - caused an OVER rich situation, making my fuel economy DIE in the butt! Changed the tank, cleaned the solenoids, and all good again.

Anyway, lot of blabber there :)

Baddad
01-03-2013, 08:49 AM
Hi Lewis,

I suspect an air bubble in one of the tires. Swap each one in turn with the spare. If that does not reveal it you have at least eliminated the tires.

Cheers

astro_nutt
01-03-2013, 09:32 AM
Hi Lewis!
New tryes and new noises..ok...sometimes tyres can have a "flat spot" from the manufacturing process. (lub-lub sound)
Also the tyre compound, being hard or soft, will make a diffrence to how it amplifies road and other noises.
Check to see if the tyres were fitted to the rim in the correct direction.
Some cars with power steering, after being on a hoist for a while, will make a shuddering noises as air would have entered the power steering fuild. This will disapear after a short while.
New brake pads and rotors have to bed into each other, conisqently during this process poor brake pedal feedback and noise are more than likely.
Good luck!

Barrykgerdes
01-03-2013, 09:48 AM
Hi Lewis

Having driven cars etc for 60+years and worked in the motor trade I have found that 95% of the worrying noises:shrug: heard when driving a car are of no consequence. A very cheap solution is an investment in a pair of earplugs.;):lol::thumbsup:

Barry

jamiep
01-03-2013, 10:10 AM
Lewis - are these the tyres?

http://www.jaxquickfit.com.au/tyres/brands/blue-streak/stiletto

Are they fitted with the correct direction of rotation (kinda obvious, but they may have put the apprentice on the job!) - it's printed on teh sidewall, but they look like a uni-directional tyre - if fitted wrongly they can kick up quite a din...

Some of these cheaper tyres can have a real harmonic drum to them - perceivable at some speeds and not others...

I've never used these and can't say I have any first hand experience with them, but if you've just had two fitted, try moving them from the front to the back and see if the noise follows....

ZeroID
01-03-2013, 11:07 AM
We run unidirectionals on both our cars and on certain roads\surfaces they can make a harmonic sound. It's to do with the tyre pattern and the road gravel size or surface ripples. There is a stretch of highway up north that for about 5 km sounds like a quiet buzzsaw under the car. turn a corner and its gone.

Turn up the radio a bit. .. :thumbsup:

Screwdriverone
01-03-2013, 03:18 PM
Hi Lewis,

Seems every time I have something done to brakes or tyres, I have had issues very soon after with bearings.

My wife's Kia Carnival had a grinding/ humming noise similar to this which turned out to be a combination of bearing wear due to loose wheel nuts (the DEALER, left them loose on that wheel to the point the rim was about to fall off) and then one day, when she reversed out of the driveway and put it in drive, the right front wheel bearing EXPLODED, sending 1/2 inch stell ball bearings rolling down the road in a greasy ballet.

I would take it back to the repairer and get them to check the bearings

Cheers

Chris

Kunama
01-03-2013, 07:46 PM
We have those tyres on one of our kids cars and they are noisy as!!
I found the best way to fix them was to turn the stereo up.

I disregard anything Pedders tell me after they told me I needed new shocks all round on my BMW ( I had just a week before fitted Bilstein Sports all round)

LewisM
01-03-2013, 09:49 PM
Took it in today. New mechanic at the joint I use.

He took one drive. Put the new tyres on back and vice versa. No difference - rules out wheels and tyres.

Took wheels off front, and checked out all the underneath - no issues with transmission, torque converter, differential, drive shafts or U joints.

And what it is? Why, it's the bloody bearings again, BOTH sides! Less than 2 bloody weeks fresh!

It had been rumbling from the SECOND they did it. I took it back the DAY after they changed the bearings and tyres. They said it was road noise (I KNOW MY CAR'S SOUNDS - it was NOT just new tyre noise) Took it back 3 days later - this time they said it was front end alignment and rear balance, so they did that (gratis). Third time I had the brakes and rotors changed. Then yesterday, and today driving I KNEW for SURE it was the bearings AGAIN.

So, the bearings had gone INSTANTLY - probably when the mech drove it. Makes me think either non-preloaded bearings, not greased, no shims or undersized/wrong bearings.

Needless to say, the manager is onto it, and is seeking warranty on the bearings. The bearings WILL be replaced by them next week.

In the meantime, I have obtained an EF Falcon from a friend - good reliable station wagon - I drove one from QLD to Perth in 4 days, with crook brakes and a leaking head, and it didn't miss a beat except for overheating coil in Armidale thanks to the oil getting on it from the leaking head :)

Screwdriverone
02-03-2013, 03:08 PM
Ahem!.....;) What prize do I win? :D

Chris

mithrandir
03-03-2013, 03:36 PM
"What's this oil can icon that started flashing today?" SWMBO has discovered that new VW 3.4L V6 engines use more oil than several year old Hyundai 1.6L ones.

I spent a couple of hours finding what oils are approved to VW504/507 spec. Then another 20 mins or so double checking bottles at SuperCheap for the right approvals.

It's not due for a service for another few thousand Km but still wanted about a litre.