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HIGH-pitch squeal, front rotor, 1/3 pedal pressure only, dealer SUCKS...HELP

20K views 57 replies 20 participants last post by  BIG SMOOTH  
#1 ·
2006 300C, 14,100 miles (that number is important...)

At about 12,000 miles I started noticing an exceptionally high-pitched whine when applying the brakes GENTLY at moderate speeds (under 40 mph).

Didn't seem to happen until the brakes had warmed up a little bit (in other words, didn't happen the first few miles/stops, but after a little bit of driving), and wouldn't happen if stronger pressure was put on the brake pedal.

Stopping effectiveness didn't change, and it was a much higher pitch than the typical "brake pads are going bad" sound, so I kept an eye...er, an ear on it.

Got worse, to the point that if I was gently coming to a stop at a red-light, I'd get people looking over.

Took it to a Dodge dealership (nearest Chrysler shop is a bit of a drive, Dodge shop is 4 miles away). They had it for 4 days for that and a vibration noise at WOT in the middle of the dash. I picked the car up, and surprise surprise, neither issue was fixed.

Took another morning off work, returned the car, had to take the "head mechanic" out with me for a drive, he claimed he couldn't hear the whine, so I rolled down the windows, he still couldn't hear it, so I had him sit in the driver's side, and THEN he heard it.

They fed me a line of sh*t about "well, it's just normal metallic noise blablabla...brake pads do that blablabla...we can try and fix it but it might get worse blablabla" and I told them to make it happen.

Came back next day, their "fix" was to turn the rotors and burnish the OEM pads (which had a ton of pad material left), which they listed on the service sheet as "de-glazing."

No surprise to me, the noise is still here.

I returned again, the Service Manager has told me that because the car is over 12,000 miles (despite that I had the issue before the magic 12K number turned on the odometer), that he could change the rotors or pads or "...whatever it is you think you want, but it'll be on your dime..." He also fed me the same line of crap again about it being "metallic particles in the brake pad will do that, you probably need to just wear them in."

I looked at him and said, "oh, you mean BED THE PADS IN?"

He looked at me dumbly.

I said "you mean, brake gently to warm up the disks so as not to shock the pads and disks, then bring the car to 60 mph, brake as hard as I can, just shy of activating the ABS, all the way to just before full stop, then accellerate again, until the brakes cool down again, and repeat that about eight times, then do it at 80 MPH? Yeah, I did that, and even threw in four runs at 100mph, being absolutely certain that the brakes were completely cool before coming to a full stop so as not to risk 'burning' brake pad material onto the hot disks which can cause noise and reduce braking effectiveness."

Then I told him for the fifth time, "I really do NOT think this is a brake pad issue, my friend, I know a tiny bit about what I am talking about."

So...I look to my fellow forum members.


Experience with this specific issue?

Is it some kind of harmonic or issue with the Rotor and not the pads?

How to fix it?

Any clue on how to address it with Chrysler? (I definitely have had enough of that particular Dodge dealership)


(PS, yesterday I had an idiot pull in front of me, had to panic stop and the car stopped like I threw out ten anchors, so the brake system WORKS fine, but this high-pitched gentle-braking whine isn't symptomatic of functionality problems, but it's driving me friggin' nuts...).


Many thanks in advance for your help.


Pete
 
#4 ·
Came back next day, their "fix" was to turn the rotors and burnish the OEM pads (which had a ton of pad material left), which they listed on the service sheet as "de-glazing."
The pads had glaze for a couple of reasons. See my comments below

I said "you mean, brake gently to warm up the disks so as not to shock the pads and disks, then bring the car to 60 mph, brake as hard as I can, just shy of activating the ABS, all the way to just before full stop, then accellerate again, until the brakes cool down again, and repeat that about eight times, then do it at 80 MPH? Yeah, I did that, and even threw in four runs at 100mph, being absolutely certain that the brakes were completely cool before coming to a full stop so as not to risk 'burning' brake pad material onto the hot disks which can cause noise and reduce braking effectiveness."
What you've done here is to combine the bedding for street pads with bedding for full race pads. It's not a case of if some is good, then more must be better. By doing the bedding at 80mph, then adding four runs at 100mph, you completely cooked those street pads. A layer of glaze formed on them and, since you don't have slotted rotors, it remained - causing the squeal at light pedal pressure and should have reduced your friction level somewhat.

Keep in mind that the energy you put into your brakes goes up with the square of the velocity. So an 80mph stop is not a 33% increase in energy over a 60mph stop. It's a 75% increase. And a 100mph stop is not a 66% increase, it is a 178% increase. (If I did the math right.)

Then I told him for the fifth time, "I really do NOT think this is a brake pad issue, my friend, I know a tiny bit about what I am talking about."
In this case, it was a pad issue.

After they deglazed the pads and turned the rotors, it became a pad & rotor issue. You've essentially gone back to square one. There is no pad transfer layer on the rotors, after they've been machined. So you need to rebed the brakes, this time only doing a series of near stops from 60mph (per: http://www.zeckhausen.com/bedding_in_brakes.htm). If the pads haven't been ruined from the abuse earlier, this should cure the noise. If it does not, then you should replace the pads.
 
#5 ·
The pads had glaze for a couple of reasons. See my comments below

What you've done here is to combine the bedding for street pads with bedding for full race pads. It's not a case of if some is good, then more must be better. By doing the bedding at 80mph, then adding four runs at 100mph, you completely cooked those street pads. A layer of glaze formed on them and, since you don't have slotted rotors, it remained - causing the squeal at light pedal pressure and should have reduced your friction level somewhat.

Keep in mind that the energy you put into your brakes goes up with the square of the velocity. So an 80mph stop is not a 33% increase in energy over a 60mph stop. It's a 75% increase. And a 100mph stop is not a 66% increase, it is a 178% increase. (If I did the math right.)

In this case, it was a pad issue.

After they deglazed the pads and turned the rotors, it became a pad & rotor issue. You've essentially gone back to square one. There is no pad transfer layer on the rotors, after they've been machined. So you need to rebed the brakes, this time only doing a series of near stops from 60mph (per: http://www.zeckhausen.com/bedding_in_brakes.htm). If the pads haven't been ruined from the abuse earlier, this should cure the noise. If it does not, then you should replace the pads.


will be my "project" tomorrow, thanks Dave.

Pete
 
#8 ·
There is a TSB for this issue if your car doesn't have the slotted rotors that upgrades you to the slotted rotors.

Unfortunately brakes are a 12/12 item and alot of dealer are pretty strict about doing anything for free if its past the warrant able mileage or time.
 
#9 ·
I have the exact same problem on my SRT8, coming from the front right wheel. I went out today and did the series of hard stops from 60 to about 15 mph. After I started feeling the breaks fade I did it one more time and then bumped it up to 70 and cruised down the highway for about 3 miles did a quick turn around without stopping and cruised back into town.

On my way home I stopped to get some gas and head that same sound again from the same wheel. Do I need to go it again or at higher speeds?

I have an appointment with the service department at the dealership I bought the car from (not a Chrysler dealership) for Friday but if they aren't going to do anything I'd rather not waste my time. Only reason I was going was because I have a 30 day warranty.
 
#11 ·
Any idea how many miles are on those pads? Did you pull a wheel and inspect the remaining thickness? The reason I ask is that pad vibration is not the only source of brake squeal. If the pad is fully worn down to the metal backing plate, then the squeal could be the result of some metal on metal action and bedding would be the wrong thing to do. Always check to make sure you have sufficient pad life remaining before you go out and bed the brakes.

I wasn't there to watch, but from your description it sounds like you followed the bedding process properly. The OEM pads do tend to be more squeaky than the aftermarket Posi-Quiet pads. So an alternative to bedding would be to try the different pads. At $167 for all four corners, it's a better alternative than buying a new set of OEM pads at well over $500. I think they want more than $300 just for the rear pads!
 
#10 ·
When we get motors in that have squealing brakes,we firstly chamfer the leading and trailing edge of the pad material(alot of manufacturers oe pads are chamfered)and this 99% of the time cures the squeal,unless is some other problem of course
 
#12 ·
I pulled the wheel last night and checked the break pads. I have 14k miles and about 3/8" of pad left. So that seems to be fine. And the squeal doesn't happen all the time, only after I've been driving for a while and then gently apply breaks. Similar to slowing down for a redlight that you see up ahead.

My only thought is do the bed in again and include a few 80 mph runs.
 
#17 ·
I pulled the wheel last night and checked the break pads. I have 14k miles and about 3/8" of pad left. So that seems to be fine. And the squeal doesn't happen all the time, only after I've been driving for a while and then gently apply breaks. Similar to slowing down for a redlight that you see up ahead.

My only thought is do the bed in again and include a few 80 mph runs.

Noticed mine again today exactly as described above and it's pissing me off to have a decent looking car and knowing everyone can hear you squealing. I've bed them in twice over the last year and think I might just get some Posi Quiet Ceramic pads and start anew. What do you all think???
 
#14 · (Edited)
I Paid So Much Money For The Pads And Rotors From The Dealer And Have Nothing But Noise Problems, Ive Taken The Car Back 3 Times Already And They Keep Shaving My Rotors, I Dont Know How Many More Times There Going Too Shave But Ibet I Have No More Rotor Left And Its Only Been 4 Months Into My New PadsAND ROTORS AND CANT BELIEVE THE PROBLEMS IAM HAVING... They Refuse To Replace Them
 
#19 ·
I could suggest when you bed your brakes, DO NOT completely stop, accelerate up to 60 mph than brake until you get to 10mph, and repeat the process a couples of time. What you want to do after bedding your brakes is to drive around without stoping for a couple of minutes too let the brakes cooldown.

If you stop the car completely after bedding the brakes without letting them cooldown first, you will more than likely wave your disks.
 
#20 ·
That's close to the right method. You want to repeat these braking events (60 - 10mph) about 8 times with no cooling off in between. And allow a few minutes of cruising afterward, to allow the brakes to cool down to the point that you can safely come to a complete stop without causing problems.

If you come to a complete stop during the bedding process, you won't "wave" or "warp" the rotors. What you will do is leave a pad imprint on the rotors. This imprint results in a thickness variation that causes brake judder on subsequent stops.

The process is explained in gory detail here: Instructions for bedding in your brakes
 
#22 ·
I took mine in for the same problem......squeal while breaking lightly. In the period of 18K, my pads were changed 4 times. Finally I demanded the slotted rotors, and they refused, until I advised them of the TSB. It was then the dealer realized they had the TSB and a full set of slotted rotors in stock. So they installed them for me.
 
#23 ·
Hey guys I've had the same problem since my recent purchase...what is the TSB on this one? (HOW CAN I GET THE #'s) I'll be taking it in for service on Tuesday and could use the info as a back-up. Thanks...
 
#24 ·
Here you go:

TSB #: 05-006-06
Date: August 2, 2006

Subject: Front And/Or Rear Brake Rotors Grooved/Scored

Models: 2005 - 2006 (LX) SRT8 Charger, SRT8 Magnum, SRT8 300C

Symptom/Condition: Front and/or rear brake rotors may appear grooved or
scored prematurely.

Diagnosis: Inspect the brake rotors. If the rotors show premature
grooving or scoring, perform the Repair Procedure.

Repair Procedure: Using the procedures outlined in TechCONNECT: SERVICE
INFO tab /5 - Brakes/Hydraulic replace the front and rear brake rotors
with the slotted rotors listed in the Parts Required section. Inspect
the brake pads and replace the pads as necessary.

NOTE: If premature grooving or scoring is present on any rotor, slotted
rotors must be installed in the front and rear.

Policy: Reimbursable within the provisions of the warranty.
 
#25 ·
Thanks for this one! Although my rotors are not grooved or scored but possibly warped? Wonder if they'll acknowledge this as the same issue?
 
#27 ·
'fraid not DZ, just hit 20k... I read your threads and articles on your page about bedding benefits but got some uncomfortable steering wheel shake under heavy breaking...any idea?
 
#28 ·
'fraid not DZ, just hit 20k...
Bummer. Not much of a chance they'll do anything for you now. But it never hurts to ask.
I read your threads and articles on your page about bedding benefits but got some uncomfortable steering wheel shake under heavy breaking...any idea?
Did the steering wheel shake spook you enough that you didn't finish the 8 near-stops of the bedding process? Or did you complete the bedding anyway and the judder was still there?
 
#29 ·
That's exactly how I would call it ... spooked!... had a car with bad rotors previous to the C and I wouldn't wanna make things any worse so I stopped after two runs. Hopefully they'll work with me and thanks again for the input DZ.
 
#32 ·
On what basis? It's a waste of your time and their money to not try rebedding the brakes first. In my opinion, there's probably nothing wrong with the rotors.

Unfortunately, many in the automotive service business do not understand all the root causes of brake judder and vast amounts of money are wasted each year replacing components, when a simple procedure on the road would likely cure the problem.

I would encourage you to develop a healthy, respectful relationship with your service adviser, rather than one based on demands and "getting loud enough" so they do what you want, just to get you out of their hair. You need to work with them for the life of your vehicle, so don't destroy the relationship over something you can probably fix yourself with a few hard stops. If you've established a good relationship with them, they're more likely to cut you some slack if your tranny blows up 500 miles outside of warranty. Poisoning the relationship over brake judder is not a good long term strategy, in my opinion.

If bedding does not work, then I certainly encourage you to take it to the dealer. But that should be the 2nd step, not the 1st step.
 
#33 ·
Hey DZ, mind if I send you a PM?
 
#36 ·
My car only has 4k miles on it, i already took it to the dealer and they sprayed stop squeek on it. They have now told me that is all they can and WILL do.

The brakes are still squeeking every single time!!! What can i do?

Dave Z will tell you to BED THE BRAKES. Check out the links he's posted on it in this thread. I got you covered this time Dave!!!
 
#37 ·
Might sound crazy!

I have an 05' 300c. As soon as i got i changed tires to yoko's. Made lots of difference. Then at about 35000 my inner tierods were bad. I got two of the last three in the united states. By the time i actually changed out the tierods my tires were bad all of them. Between that time i got my front rotors turned down. I just put new tires some hankook at 56000. I left the place where i always go. And could still feel brakes acting up. So when i got home i took each rim/tire off and used about three cans of non-chorinated brake cleaner on every part for each. So i used twelve cans total. It made a huge difference, i still have the oem rotors front and back and still have oem pads front and back. Never de-glazed or anything. Now i did do this bedding thing i heard of. My 05' 300c rides and brakes like brand new actually better than when i bought it. Hope this helps. I hated the brakes when i first got it but now they are great for lasting that long. They still got lots of pad on them.
 
#58 ·
....not as bad as before I bed them in for a true second time but a slight slight squeal still remains, WTF!!!! I think I'm gonna say screw it and go with some Posi ceramic pads.

I finally did it today.


Yup, that sounds 'bout right, good for a few days then back again. I've got drilled/slotted rotors and Posi Extended Wear pads so I don't get this whole squeal issue. I'm just gonna start anew with new ceramic pads.

As stated above, got the Ceramics up front so we'll see how these respond and then maybe change the rears in the near future too.

Finally heeded your advice Dave Z and got the PQ Ceramic pads, I'll let you know how the are as the miles add up.
 
#40 ·
I've bedded mine in 3 times and they are good for about 2 days and then it starts all over again, but only on the front passenger side though. I'm just ignoring it until I need to replace the pads. And I'll install the slotted rotors as well while I'm at it.

Yup, that sounds 'bout right, good for a few days then back again. I've got drilled/slotted rotors and Posi Extended Wear pads so I don't get this whole squeal issue. I'm just gonna start anew with new ceramic pads.
 
#44 ·
I have a 2005 300C I bought new in 2004. Had break problems and the dealer replaced pads and rotors at around 15K for free, things were fine. Now at 50K front end shimmy at high speed breaking. My repair place (not dealer now) said two front rotors were out and put on new ones. Shimmy gone but now I have squeeling at light breaking. Repair shop said nothing they can do but I should work them in hard. Remembered the Bedding thing here and went out and did it yesterday. Much better today - will see over time. BTW the shop says I have plenty of life on the pads (don't know if 50% or what - hope not an issues for bedding). Whats all this about TSB and slotted rotors - thought that was just for SRTs. If the bedding doesn't hold may try it again and just do the quiet pads when I need them - not buying more rotors. What and where do you get these pads.

Bob