Front Brake Creaks! (Not squeaks)

[MLC Stang]

Guys,

My left front brake creaks! Not squeaks, but creaks like an old worn out wooden rocking chair! That’s the best description of the sound that I can provide.

The car does not even have to be moving to check this. Just sit at idle in park and press the brakes on and off, and creak – creak – creak – creak !!! I can’t quite figure out what part is causing the noise.

My front brakes are ‘99 and up GT dual-piston PBR replacements. All new parts (not from junk yard) when installed a couple of years ago. They still work great, but now the left front creaks. No pulling to one side or the other.

Any ideas on where to look, what to check, for the cause would be appreciated.

 

[HISSIN50]

Are you sure it's not a bushing (the brake being applied compresses the suspension, causing the squeak)?

I've run into it on another car but will hold off with saying anything - I dont want to get this thread off on an incorrect course.

 

[MLC Stang]

Are you sure it's not a bushing (the brake being applied compresses the suspension, causing the squeak)?

That's exactly what it sounds like, and that was my first guess.

However, it makes the exact same sound when standing still in Park in the garage and then applying the brake. There's no compression of suspension involved in that test at all. (Plus, I can push up an down on the left front fender all day long trying to make the suspension creak, and it doesn't.)

I'm clueless...

 

[Zero_chance]

I think your best bet would be to put it on a jack, take off the wheel and put your head in by the caliper and try to pinpoint where its coming from.

 

[HISSIN50]

Ok, gotcha. I do agree with ZC about getting it safely in the air and having an assistant push the pedal while you watch the caliper.

Given it happening with no static load, I have a feeling it's the caliper slide pins. They're like 7 bucks/side at the parts store (not very great quality if an overseas version in my experience). YOu can just pull yours and clean them up and regrease them to see if that fixes it. They have a sacrifical coating (Cad or something similar to it) that eventually wears off. It's kinda like what teflon is to cooking pans.

Interesting issue.

 

[MLC Stang]

Thanks much for the feedback!

I guess I'll get the wheel off, stick my ear to the caliper and listen.

If it's creakin' from there, I'll disassemble the caliper, pull the caliper slide pins out and take a look for some obvious signs of wear or galling of some sort on the pins.

If I lube the slide pins what should I use? Plain old grease, lithium grease, wheel bearing grease, or what?

Thanks much for the feedback!

 

[reddy351]

Amy kind of "waterproof" grease. The kind for boat trailer hubs is good. I have a tube of white lithium, though. Works good, too.

 

[HISSIN50]

I personally like to use high temp brake grease (a dedicated product). What I like about it is that it's real sticky and doesnt seem to thin out with heat - the thought of runny grease around brake pads and rotors worries me.


That said, Rob's obviously had good experiences with other products.

If that's not it, I'm sure once your head is buried two incehs from the noise, the source will be real apparent (or it won't make the noise once the car is in the air - that's how it goes for me).
Greasing or replacing those slide pins is something I do with regularity anyhow (it's not like you're wasting your time).

Good luck.

 

[Zero_chance]

Yeah Im interested to know what you find out once you can get in for a closer look. Keep us updated.

 

[MLC Stang]

Well, I got the car in the air this weekend and pulled the wheel off. And, luckily, it did make the same creaking noise.

I checked the torque on the two anchor bolts that hold the whole brake assembly onto the spindle (85 ft-lbs). Those were OK. I checked the two bolts that screw into the guide (slide) pins that hold the caliper on (25 ft-lbs). Those were OK as well. So... nothing was loose.

Next had my wife press the brake pedal on and off and literally stuck my ear right on top of the aluminum caliper housing. That's definitely where the noise is coming from! As the brake pedal gets to the end of its travel and full hydraulic pressure is applied it makes that creaking noise until you can' t press the brakes any harder, then it stops.

Since there are no loose bolts it must be the motion of the caliper assembly on the guide (slide) pins. I did not have the time necessary to completely remove and disassemble the whole thing this afternoon. (Didn't have the new guide pins either!) So, will have to buy some new guide pins and replace them another day.

Thanks again for the help.

 

[87_GT]

well def. keep us posted. i am having the exact same problem with my 99+ pbr brakes as well. so once you find out what needs to be replaced it will be of great help to me.

 

[HISSIN50]

Nice work. It's nice when an issue is ongoing even when you're actually lookin for it.

It only takes a few mins to swap the pins out. They can be kinda turdy to get in and out of their booties - that's the toughest part. The new pins even come with threadlock most of the time.

 

[go-stang5.0]

I agree with hissin in the brake caliper grease, you dont need a lot either. One time I used cheap grease (prolly too much too) and i had it seep out as the caliper got really hot on a track day and it ruined a set of track pads and rotors. You prolly dont open track the car but I bet if you having fun on the highway and you have to bring speed down in a hurry, something of the like can happen to you too.