Rattling under car

venomx

Few weeks back my car developed a rattle from underneath the car.
As soon as you apply the brake, it goes silent which would indicate the brakes right? 
Pads and discs are brand new, so I'm thinking the slider pins in the caliper.

Took the car down yesterday  and they said the front bottom ball join has play, so they replaced the front lower arm.

Even though Arm pin and bush was replaced 5 months ago.

It is still making the noise so not happy I just spent about £140 for that.

I'll be taking it back down this week.

Any advice? 

dogshome

With a 'rattle' rather than a knock or thump, the first thing I'd look at would be the Exhaust system

angrycrow

Check all your exhaust heat shields are firmly secured. The round clips rust off or the heat shield breaks around the clip. Clips are a couple of quid on ebay and just push on. If the heat shield has broken around the clip put a large washer between the shield and clip. 

venomx

angrycrow said:

Check all your exhaust heat shields are firmly secured. The round clips rust off or the heat shield breaks around the clip. Clips are a couple of quid on ebay and just push on. If the heat shield has broken around the clip put a large washer between the shield and clip. 

Thanks for the advice.
I've already secured the heat shield so it doesn't have any contact where it could wobble. I have also secured the under tray. All the exhaust mounts are in tip top condition.

The fact the rattling disappears as soon as you even lightly apply the brakes would suggest the slider pins, no ?

I'll take it back down to the mechanic this week 

Phantom151

venomx said:

angrycrow said:

Check all your exhaust heat shields are firmly secured. The round clips rust off or the heat shield breaks around the clip. Clips are a couple of quid on ebay and just push on. If the heat shield has broken around the clip put a large washer between the shield and clip. 

Thanks for the advice.
I've already secured the heat shield so it doesn't have any contact where it could wobble. I have also secured the under tray. All the exhaust mounts are in tip top condition.

The fact the rattling disappears as soon as you even lightly apply the brakes would suggest the slider pins, no ?

I'll take it back down to the mechanic this week 

Does it get noticably worse when you drive over a pothole? I'dbe surprised if it was the sliders but take a look at where the brake pads sit on the carriers. There should be some shims stopping up and down movement of the pads. I had one missing on mine once and it was a !!!!!! to solve as it isn't obvious if you don't know they should be there.

Goudy

How bad is the rattle?
Is it quite loud and felt across the axle?

If so you might have an anti roll bar drop link that's worn.
It's fairly common for them to rattle when worn. 
They can sound like anything from a muted and soft rattle to a loud knocking that sounds like something major it about to fall off!

As the anti roll bar connects the wheels on the same axle together, you often get a feeling the knock/rattle is across the axle.
So the rattle might be on the near side, but driving over a bump with the off side wheel still causes the near side to rattle.

Quite often you notice if you alter the pitch of the car in a certian way the noise tends to alter or vanish as the altered pitch from cornering or braking pulls or compresses the slack in the worn drop link joints.

Worn drop links are difficult to spot as if you jack the car up with the weight of the wheels hanging to check them, it pulls all the slack out of the worn joints so they appear fine.

Best point the steering dead ahead when they are on the flat ground and slide your hand around the back of the road wheel, grip the link and try rattling it.
Any free movement in the link, even the smallest amount will cause a rattle or knock.

venomx

Right. Had a look today at it seems as though the " stone shield " behind the disc was rattling around and making contact with it. Moved it away gently and now it seems to have disappeared. Will keep an eye on it

Noise is quieter but still there.

I'll go back to the mechanic and see if they can help.

 

Thanks anyway !

venomx

Mechanic had a look, nothing loose or wrong. However, they have stripped, cleaned and lubricated the brakes. Noise is now gone ​​​​

diystarter7

I read the thread late I was going to suggest have a free brake check and tell them about the noise. 
A few years back I thought our daughter's car was not sounding right and made a grinding sound. The car had been parked up for a few months as our daughter was working abroad. Any on that day I not only started the car up but rand it down our quiet road and it did not feel right. Kwikfit do a full brake check and the young man cleaned it etc and all good, no cost to me. They also reassured me the brakes had 90% left in them inc the discs. 

At times a free brake/exhaust check can sort out the problem. IMO, a garage is only as good as the people that work there.

Grey_Critic

When the Ford Focus started they had problems with reported rattles. Investigation showed that a heat shield above the exhaust was concave and pebbles thrown up sat in there and so the rattle - simple design fault that caused a lot of problems.