Brake CLACK!

[RandallNeighbour]

My big concern at the moment is when I'm parking my car in my garage and I roll back and hit the brakes hard. I hear a loud crack or clack.

It's not always been this way, and I makes me concerned that my brakes may NGO serve me well in a time of great need.

I replaced the drop links thinking that might be it. And I inspected the calipers and pads and springs and pins.... All ok and tight. I have sway bar bushings to swap out one weekend soon, but there's no play in the ones on the car now.

Thoughts? What should I look at next?

[shadrach74]

How did you "inspect" your calipers? I have seen cases when calipers (including my own) under very modest braking (which still generates a load that a man would require a large pry bar to replicate). Unless you did a very thorough check of the calipers, i would still bet on a loose caliper. Do let us know what you find.

[RandallNeighbour]

I actually yanked hard on the passenger side caliper, but you've got me wondering now. I had to put a timesert in the top bolt receptacle on both sides in the wheel carriers because it was rusted at the tip and totally stripped it out upon labored removal.

I wonder if the passenger side has given way.

[thstone]

Save your money.

I have brand new shocks, springs, front and rear sway bar bushings, front and rear end links, lower control arms, rear toe links, and front and rear upper shock mounts along with new brake rotors and pads. Brake calipers were torqued to spec when I replaced the rotors/pads.

I STILL hear that "crack" sound when reversing and hit the brakes so I've just learned to live with it.

[Mark_T]

Could it be related to your ebrake? Perhaps you could try backing off the adjustment so the pads are nowhere near contacting the drum and see if the noise goes away.

[shadrach74]

It's amazing how little it takes to make a racket with breaks. I went through a similar situation with my GS400 DD in the process of seeking out the clank, I discovered axial movement in my upper control arms. I removed the old and installed new ones. Imagine my surprise as I was backing out of the garage after completing that 5 hour job only to hear the dreaded clank. I did not have any movement in the caliper when I tried to move it by hand. But as I said, there is no way a man can replicate even light brake force without an implement. Anyway, I pulled a Tstone and just lived with it. This turned out to work well, because it got worse and worse to the point of clanking on rough roads. I thought I needed new struts, but I could not replicate the noise with up and down movement with the car stationary. Then I thought it was the sway bar bushings,but they turned out to be fine.... Once the symptoms were bad enough it was an easy to see the problem was in fact a caliper that was moving a few mm. Even then, it was not what I would call loose feeling until I really wrenced on it. Always use Loctite blue on caliper bolts.

[healthservices]

does it happen only after you change directions and the first initial brake application in that direction?

[stateofidleness]

Originally Posted by healthservices

does it happen only after you change directions and the first initial brake application in that direction?

mine does this! started after my first DIY brake pad change. everything went back in with ease and no "issues" were encountered, but if I go from Reverse to Drive, the very first time I brake (hard or soft, doesn't matter), it makes a noticeable "click" as if the pads are seating against the rotor or something. Any time after that there's no noise.

What causes this? I've been too lazy to check myself. My brake functionality doesn't appear to be affected at all. Still stops on a dime.

[RandallNeighbour]

Originally Posted by healthservices

does it happen only after you change directions and the first initial brake application in that direction?

Yup. I think so.

[stephe57]

What I've seen typically is there are brake pucks or adhesive disc called "damping shims" that are attached to your original pads. When you removed the pads they will sometimes stay in the caliper cup and more often then not they come out with the pads as they have an adhesive backing. These "pucks" do not allow the pads to shift back and forth in the caliper. Just a thought as I have performed many brake services and most recent being a 993 in which I remember them coming off rather hard.



-Ty

*Speed Yellow 986*

[RandallNeighbour]

So should I pull my pads and see if this part has fallen out?

[stephe57]

Well if its not the first brake service this cars received then it very well could be that they've been removed. If you want to pull one side out and see if there in the piston cup then by all means. They may be there but the adhesive may be "soiled".

-Ty

*Speed Yellow 986*

[DFW02S]

Originally Posted by stephe57

What I've seen typically is there are brake pucks or adhesive disc called "damping shims" that are attached to your original pads. When you removed the pads they will sometimes stay in the caliper cup and more often then not they come out with the pads as they have an adhesive backing. These "pucks" do not allow the pads to shift back and forth in the caliper. Just a thought ....

That's a really helpful post for your 1st or 2nd.
If they're all this good, you'll be a legend by post 100!

[thstone]

Originally Posted by Mark_T

Could it be related to your ebrake? Perhaps you could try backing off the adjustment so the pads are nowhere near contacting the drum and see if the noise goes away.

Done that. No joy. Same noise.

[stephe57]

Originally Posted by DFW02S

That's a really helpful post for your 1st or 2nd.
If they're all this good, you'll be a legend by post 100!

I dont know about that . But Im almost positive the noise your hearing is the brake pad shifting back and forth in the caliper, thus making the audible click when going from reverse to drive or drive to reverse. Check it out, see if those damping shims are in there if not, I'm going to be pulling my 986 into the shop today and ill take a look as I'm still on the original pads. If mine are there I'll take some pics.

-Ty

*Speed Yellow 986*

[clickman]

I've had this happen on and off for years now. Never could find a reason. Caliper is tight...

[bar10dah]

Originally Posted by stephe57

but im almost positive the noise your hearing is the brake pad shifting back and forth in the caliper, thus making the audible click when going from reverse to drive or drive to reverse.

+1

.....

[healthservices]

Originally Posted by healthservices

does it happen only after you change directions and the first initial brake application in that direction?

Originally Posted by RandallNeighbour

Yup. I think so.

brake pad play, or play in the mount bolts for the caliper loose.

most likely brake pad play.

[jcb986]

Randall, it could be a motor mount problem, think about it.:ah: