Caliper Rattle?

[ET16]

I’ve been trying to track down the cause of a right rear rattle on my ’02 Cougar. First I thought it was the sway bar link: replaced that—didn’t change the noise. Then I thought it was the struts (and so did a mechanic)—replaced those—didn’t change the noise. Then I notice while changing rotors on the back that some clips were missing on the back pads on the left side: put those one—didn’t change the noise. Now the shop that put the struts on thinks that it’s the strut mounts and wants to change those. I agree that these are likely culprits, but I have one reservation: the rattle pretty much goes away while braking. Now I’m wondering… maybe a bad caliper bushing? The rear calipers on these cars have one fixed, top bolt/bushing, and the bottom of the caliper rides on a pin that is held in by a cotter pin. I’m thinking now that the caliper itself might be rattling on this lower pin. The top bolt is tight, but as I said I’m now wondering about the bushing. It leaves the other question, though. If the strut mount is bad and rattling, how could it improve while braking?

Anyone have any experience with these? Thanks!

 

[Eddie]

I have no experience with this particular issue. However, when things are stressed (like in braking) you put forces on components and that can cause a release of increase in force on those components. My question is, since the struts were replaced, why was the strut mounts not inspected? I believe it is quite possible that the strut mounting plate is at fault. JMO Ed

 

[ET16]

Eddie,

I discussed the mounts with the service adviser before doing the job, and he told me that they usually reuse them. I don't know whether the mechanic inspected them when they were off. I can see now that it's false economy not to replace them when everything is apart.

 

[pzev]

Check your center caps! I used to work at a brake test facility, and one of their test cars had this rattle or tick while driving. Couldn't for the life of use figure out what it was...until someone off the cough mentioned inspecting the center caps. Sure enough, they were rattling.

 

[AdRock]

I agree with checking the centercaps.

Also, with that rear tire off, flick the backing plate and see if it rattles.

I had a rattle on my stang on the drivers side rear. One of the rivets on the backing plate had worked itself loose and the plate would rattle like mad on the highway.

 

[ET16]

The backing plate seems fine. How do I check the center caps? Aren't they just pressed in?

I thinking now that there might be a problem with the main bolt and bushing. The left side (problem side) is a rebuilt caliper, and I'm thinking that maybe there was a hardware mistake. A caliper is $46, so I just may change it out to see what happens.

I still wonder about the strut bushing, though...

 

[ET16]

So I finally solved the mystery. It was the pads themselves rattling in the bracket. I changed the pads with ones with clips, and the rattle disappeared. It's a little strange that the other side didn't rattle, but it seems that the bracket might have been worn on the rattling side.

 

[mechtech2]

More than once I have been baffled by a sudden-onset rattle noise in my cars.
And more than once it has been the ice in the fast food cup jiggling around!