C30 General : Strange vibration coming from offside front.

[Minimad]

Hi All,

I'm in need of some help to diagnose a problem on my 2010 C30 1.6 D2.

In the last couple of months a vibration has started, emanating from the front drivers side. I've had the front wheels rebalanced and its still there.

The problem seems worse when the car is cold, but is definitely still there after driving for sometime. It is only there when driving in a straight line and 100% disappears when turning either left or right.

Before I go spending money on cv joints and driveshafts, I'd just like to see what people think it could be. Inner cv sounds most likely to me. The noise is a dull low frequency knocking/vibration equal to road wheel speed.

Any help and thoughts appreciated.

Mark

[cjj]

First stage with these things is to check your tyres.

Cupping on the edge of the tyre can create all sorts of symptoms, and is easily checked

[Minimad]

Tyre wear is even across the tread, and the tyres are all correctly inflated.

[cjj]

Originally Posted by Minimad

Tyre wear is even across the tread, and the tyres are all correctly inflated.

Just to clarify (and to double check), cupping or feathering can be quite discreet and isn't really about the wear, but the step from tread to tread (in the direction of travel, rather than across the tyre).

Hopefully that doesn't come across as patronising, just want to be fully sure you're getting where I'm coming from.

The next step I'd be looking at would be to check to play on that wheel. Rotational play can be anywhere along the driveshaft to the hub itself, and you should be able to feel it if it's got to the stage where it is producing a pulsing vibration.

It's mainly a process of elimination, but if it's been going on for a while and is not effecting the wear on the tyre, it means there's a pretty good chance it's nothing related to the suspension or bearing, and you may be on the right path by suspecting a driveshaft issue.

[julianps]

Originally Posted by Minimad

Hi All,

I'm in need of some help to diagnose a problem on my 2010 C30 1.6 D2.

In the last couple of months a vibration has started, emanating from the front drivers side. I've had the front wheels rebalanced and its still there.

The problem seems worse when the car is cold, but is definitely still there after driving for sometime. It is only there when driving in a straight line and 100% disappears when turning either left or right.

Before I go spending money on cv joints and driveshafts, I'd just like to see what people think it could be. Inner cv sounds most likely to me. The noise is a dull low frequency knocking/vibration equal to road wheel speed.

Any help and thoughts appreciated.

Mark

cjj will cover the basic engineering issues; as commented in multiple paces here, the lower wishbones on this chassis (S/V/Focus, etc), especially the bushes, can go off by 50,000 miles.

Normally comes up with different symptoms but, as you're there, you might want to to check them too.

[Minimad]

Ok so a brief update on this very annoying problem.

I have changed both front wheel bearings, was very straight forward, apart from needing a hydraulic press to get the old bearing out and the new bearing in. Luckily I work for a well known midlands based 4x4 manufacturer and got the helpful guys in one of the tool rooms to lend me their press for 15mins.

New bearings back on, and the noise is still there, but a bit lower in volume. When I had the hubs off, I gave each half shaft a good inspection, the CV boots are in excellent condition; no tears or signs of leakage; and no excess play.

I have now decided to focus on the wheels themselves as the cause of the problem. It could be an out of balance wheel; out of round tyre or bent or buckled wheel. So tonight I will swap the wheels front to back, and see if the noise moves. I will also have the tracking done to make sure the wheels are at least point in the right direction.

Failing that, I am down to thinking that it could be diff related as it is directly related to road wheel speed, it even occurs when in neutral and rolling down a hill.

Does anybody have any other ideas? Or does anybody have experience with misshapen tyres or worn tyres causing the problem. This is turning into one of those very annoying problems.

[Alajota]

Bump

Is this now sorted, as I seem to have the same issue.
Will/ might know what the issue is sometime this week

[Minimad]

Yep, problem has been sorted. Short answer, it was the tyres. Somehow they had gone out of round, even though the car was used everyday.

I had the tracking checked and the guy in the garage said it was spot on, so it couldn't be the tracking. I talked him through the issue and he suggested putting a dial on the outer circumference of the tyres and turning the wheels.

Upon doing this it was seen that the tyres were no longer round, how this happens on a car that is used everyday I don't know. It sometimes happens on my classic mini when it stands for a month or so over the winter, but I've never had it happen to a 'normal' car. And the tyres were Pirelli's so not a cheap brand.

Anyway, put some new boots on the front and the noise was gone! Finally!

[vzh7gk]

Rubber band low profiles...

[Austin160]

I think there is a valuable lesson here. I think vibration should always be blamed on tyres, unless positively proved not to be. It's a matter of safety to owners and others. Does it depend on the opinion of one tyre fitter to be able to thoroughly inspect a tyre for defects, rather than just sticking it on the balancer for rebalance? Costly oversight too it would seem, but at least you are now safe.