Vibration and noise.

[Bonk]

Spoiler here. Tl/dr don't bother reading any further.


Ok, this is a difficult question to answer definitively on an Internet forum. Sound is subjective so we all have a different perception of it and both sound and vibration can fool you quite easily as to its source. I know this as I work for an acoustics company.

My problem is a slight graunching/vibration between 15 to 35 miles an hour. It's there in 2 wheel drive and 4 wheel drive and it increases with speed, not engine revs. It's slightly more pronounced when not accelerating or slowing down but it's not the brakes, it does it if I'm not braking.

The vibration goes away after 35 mph but the noise doesn't. The noise, though difficult to explain, sounds like a light howling, is sometimes constant and sometimes goes in cycles.

I've trawled the threads, everything from cv joints, bronze bushes, wheel bearings (front and back) prop shafts, ujs etc etc. I can't find a definitive answer, too many opinions.

Now this is what I've had done so far after the noise started. Adjusted both front wheel bearings. Had new wheels fitted (didn't think this was the problem but wanted new wheels anyway) balanced, with track rods changed. Greased the ujs on the prop shaft and greased every nipple I could find. Had the brake pads checked and they're fine (I thought they would be as I changed them recently).

Anyone that read that lot deserves a medal but any ideas would be greatly appreciated.

Thanks for taking the time to read. Please discuss and answer.

[marcdtr]

I had a fault like this and found it to be a worn stub axle due to a failed wheel bearing in the past. I replaced the bearing then refit and the caliper rubbed the disc it was so bad. On replacing the stub axle problem solved. Where the bearing was tensioned onto the stub axle it was not sitting true.
Worth taking a look hope it helps.

[Dobbslc]

I've had this on a Ford Cougar I replaced wheel bearings checked the brakes etc it was a tyre out of true, it was balanced but it had worn funny.
I also had something similer on the Surf I really noticed it in france within 1 mile of leaving the ferry as the roads are very smooth as. (they spend their tax payers money on the roads you see not lazy work dogders welfare payments).
It was a tyre out of round by 10mm!
Jack the truck up and check them.

[Bonk]

Thanks for the ideas so far.

Rear tyres are brand new and the fronts are almost new so I don't think it will be that. Also, they may make a noise but it wouldn't explain the graunching/grinding that I'm getting.

Just to add, the noise is no worse but the grinding/graunching is getting considerably worse.

Any other ideas would be gratefully received.

[Bonk]

This will be no use to anyone but I thought I'd better close the case.

I took it to the garage and left it with them for a day. Picked it up at five o'clock and was told they couldn't find a problem. Wait for the mechanic, I was told, and he'll come out for a drive with you so you can tell him the problem. I waited, he was out on a call. An hour later he wasn't back so I said I'd pop back tomorrow and go for a drive. All good.

Take it away from the garage and it's driving like brand new. Now I'm confused.

I went back the next day and asked if he'd done anything, anything at all, like put it on the ramps and have a poke about. Nope, nothing. He just drove it and couldn't find anything.

They didn't charge me anything, the problem seems to be solved and they told me to bring it back straight away if the problem comes back.

If anyone wants the number of this magic garage message me.

On a serious note, I'm completely stumped.

[popuptoaster]

Might have been some mud or a stone or something stuck inside the wheel, could throw it out of balance and catch on a the brake calliper, maybe it just fell off.

[tashtego]

This will be no use to anyone but I thought I'd better close the case.

I took it to the garage and left it with them for a day. Picked it up at five o'clock and was told they couldn't find a problem. Wait for the mechanic, I was told, and he'll come out for a drive with you so you can tell him the problem. I waited, he was out on a call. An hour later he wasn't back so I said I'd pop back tomorrow and go for a drive. All good.

Take it away from the garage and it's driving like brand new. Now I'm confused.

I went back the next day and asked if he'd done anything, anything at all, like put it on the ramps and have a poke about. Nope, nothing. He just drove it and couldn't find anything.

They didn't charge me anything, the problem seems to be solved and they told me to bring it back straight away if the problem comes back.

If anyone wants the number of this magic garage message me.

On a serious note, I'm completely stumped.

Same thing has happened to me a couple of times, with different cars. I'm told its usually bits of debris stuck in the wheels somewhere, mostly between the disc and callipers...the vibrate or rub at certain speeds/revolutions. Sometimes they move slightly and the vibration or noise gets worse. When they get dislodged or disintegrated the noise disappears.
Cheers

[Bonk]

That's what it must have been.

Cheers fellas.