Droning Noise - Help!!!

[Tooks]

Ok, symptoms are;

30mph+, droning noise starts and gets louder up to about 60mph.

I've got a spare set of wheels and tyres, so changed those in case it was tyre noise - no change.

At 50mph, I can switch off the engine, then turn the ignition so I've still got steering etc, droning is still there, so rules out engine noises I guess.

The droning drops with road speed.

Local VAG specialist thought it could be a wheel bearing, so spent today dismantling the drive shafts on the front so he could listen to the hubs/bearings, thought the OSF was noisy so changed the wheel bearing - droning still there... Aaargh!!

So, I'm left with changing the left hand side, or turning my attention to the expensive oily bit called the gearbox and differentials! The noise is definately road speed related though, it doesn't change pitch with changing gears or anything. It's still there with the engine switched off, in neutral and coasting to a stop. Could it be prop shaft bearings (I confess I don't even know if there are any!) or even CV joints or similar?

I did try the long left or right sweeper test to see if the droning changed pitch under left or right cornering, and I'd kind of convinced myself it changed when I went round right handers, but not sure really.

Any pearls of wisdom before I chuck even more money at this thing?! HELP!!!!

 

[murran]

if it seems noisier on right handers then usually it points to the n/s bearing. you sure its one of the fronts?

 

[Tooks]

Thanks for the reply, much appreciated, this is all quite stressful!

If anything, it was a little quieter on right handers, but the guy in the garage did say the wheel bearings were twin race things, so it might not be much help diagnosing?

The noise definately seems to be coming more from the front, but I know sound can travel on cars and send you on a wild goose chase.

I'm worried now that it's the middle, although the garage did say they would suspect the rears next.

He took the driveshafts off the front on the ramp and span the wheels, and reckoned the NSF was quiet, but the OSF had play and was noisy. The car has done over 100,000k, so I suppose all the bearings could be well worn. His feeling with bearings though was 'if they aren't broke, don't try to fix them'! He did say the NSF was a little tight, which might mean it could be noisy? He basically only had the time to fix one today (he also did the alternator pulley/bearing thing as that was seized), and thought the OSF was the worst.

I'm also thinking this has really only come on the last week or so, about 2 weeks after a remap, so I wondered if it was just coincidence or related...

 

[scott b]

i had the same problem on mine, 25 mph+ droning noise, turned out be a wheel bearing, picked the car up today from getting it done

 

[Tooks]

I'm really hoping it is something as 'simple' as that scott b, I really am! I've spent a lot getting the car to a state where it was just about right these last few months, so the last thing I need is something like a gearbox to go up the swanny!

How much did they charge you for it if you don't mind me asking, and how did they diagnose which one?

 

[scott b]

diagnoised it meself, just got me mate to comfirm, cost £120 supplied and fitted, cash price, also just had the cv boots replaced and all the top links, drives so much nicer

 

[Tooks]

Ok, I think I'm going to go ahead and get the other one changed, for the sake of £150....

Any other ideas anybody if it isn't that?

 

[markA4tdi]

do 61mph !or turn the volumn up on the stereo lol
on a serious note though, a car thats done over a 100k is going to be worn in some areas and have some noises, every car has them, you could wait for the problem to get worse and then spend money on it, rather than spend money on replacing things what dont need doing.

 

[Tooks]

Hi, thanks for the post!

I do hear you regarding the wait until it gets worse thing, but the car was quiet and refined until about 10 days ago, so whatever it is has come on quite quickly.

I understand the gearboxes are pretty strong, but as the noise doesn't change with gear changes, I'm pretty confident it isn't the gearbox. I'm not sure what else it could be though.

I really wish I could ignore it, but it's too loud!

 

[scott b]

with mine it was worse when going on a right hand bend or round a round about, even with the car in any gear and also with the clutch dipped the noise was still there, noise now gone

 

[Tooks]

Ok, bit more info.

I just took my car to a local farmer, who has a car ramp. I raised it off the ground so all four wheels were free to rotate, and stuck it in 5th gear and had a good listen.

There is a lot of grumbling coming from the near side rear bearing and I thought I could detect a tiny amount of play. Road testing again afterwards, the noise peaks at 55mph, and now that the roads are finally dry round here I can detect that the noise does go quieter in sharp right handers. That would fit wouldn't it, ie it's loading the left rear?

The only thing that's throwing me is that the noise appears from inside the cabin to be coming from the front, but I guess any noise could resonate along the driveshafts/props etc into the body...

Blooming car!!

 

[markA4tdi]

sounds like a wheel bearing to me, when a bearing goes there isnt always play felt at the wheel, you said that you thought the sound was quieter when taking the load off the offending wheel, does the noise increase when putting load on it? if it does i would put money on it that this is the problem your experiencing, its just a shame that the garage you first took it to, didnt diagnose it. i recently did the wifes rear wheel bearing as this was happening to her clio, £9.98 later and an hours time, no noise! checked on how much renault would of charged to do this £179 !