When applying brakes hear a grinding/rubbing/thud noise
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2004 CLK 500 with AMG Package, Not Convertible
When applying brakes hear a grinding/rubbing/thud noise
Guys,
I don't drive my car daily, maybe after every couple of week. So rotors get a bit of rust on them.
If I hit the brakes too hard, I am hearing a slow grinding/rubbing/thud kind of sound, coming from driver side(not sure if front or rear). If I apply the brakes in steps/slowly, then noise isn't obvious.
I do have all brand new tires too, not sure if it has anything to do with it?
Any idea or input what this noise could be?
I don't drive my car daily, maybe after every couple of week. So rotors get a bit of rust on them.
If I hit the brakes too hard, I am hearing a slow grinding/rubbing/thud kind of sound, coming from driver side(not sure if front or rear). If I apply the brakes in steps/slowly, then noise isn't obvious.
I do have all brand new tires too, not sure if it has anything to do with it?
Any idea or input what this noise could be?
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You could have a piston that is locking-up. I'd pull the wheels and check everything for proper operation. if the pads are still good, remove them and apply some anti-squeal lubricant to the back of them where they meet the pistons. Also, clean, polish, and lube the slides/pins that the pads travel on.
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2004 CLK 500 with AMG Package, Not Convertible
You could have a piston that is locking-up. I'd pull the wheels and check everything for proper operation. if the pads are still good, remove them and apply some anti-squeal lubricant to the back of them where they meet the pistons. Also, clean, polish, and lube the slides/pins that the pads travel on.
That's what I fear too. I have made sure pads look fine, at least from the outer side. They have enough meat on them.
Both rear rotors are NOT as clean(rust free, have some very small rust) as front ones. Does it mean piston is locking up? If so, could it be the reason for noise coming from driver side?
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You might try describing the noise more specifically. "Grinding/rubbing/thud" is hard to picture - usually a thud does not accompany grinding or rubbing. But the light rust that forms on rotors - even in a few minutes of rain or at a car wash - will be gone in just a few minutes of driving. If your rears stay rusty, you have have a frozen caliper, but two freezing up at once seems unlikely because it's not that common of an occurence.
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2004 CLK 500 with AMG Package, Not Convertible
Thanks Yidney. Let me try explaining it, it's like when any of your car is on dirt/gravel, it makes a noise, it's very close to it.
It's a very fine thin rust, please see pict for all rotors.
I drove the car for almost 10 miles over the weekend and that's how it sits right now.
It's a very fine thin rust, please see pict for all rotors.
I drove the car for almost 10 miles over the weekend and that's how it sits right now.
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2006 CLK350
The first 2 pics look like the rotor is scored some. Not bad but it looks like something is going on there. I would pull the pads and at least take a look.
You were asking about a piston sticking. If your piston was stuck or something your car would be pulling to one side under braking.
You were asking about a piston sticking. If your piston was stuck or something your car would be pulling to one side under braking.
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2004 CLK 500 with AMG Package, Not Convertible
First two are for rears rotors and last two for front ones.
I don't feel a pull or anything at all. Should I pull ONLY rear ones or front ones as well?
Thank you.
I don't feel a pull or anything at all. Should I pull ONLY rear ones or front ones as well?
Thank you.
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From: Huntington Beach, CA
2006 CLK350
which ones are the first 2 pictures? They are the ones I would be initially concerned about. But really get in and look at the inside pad. I have experienced uneven wear between the inner to outer pad on cars before indicating a problem.
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2004 CLK 500 with AMG Package, Not Convertible
If you look at the thread, 2 pict on left are rear ones and two on the right are front ones.
What if there is an uneven wear? Does it mean piston is shot or? Is scoring seems too bad?
What if there is an uneven wear? Does it mean piston is shot or? Is scoring seems too bad?
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From: Huntington Beach, CA
2006 CLK350
In my case the uneven wear was just that whoever had done the previous brake job on my car had not cleaned up and lubed the sliders and surrounding hardware. Everything moved easily after cleanup so I reassembled and all was well.
If you know what you are doing and have the tools to compress the piston again you can have an assistant VERY CAREFULLY AND SLOWLY press the brake pedal and watch the piston extend from the bore to see if you see any falter as it comes out. If it hangs at any point you can either replace the caliper or disassemble it, inspect it for scoring and clean it up. It is a lot easier just to replace it. I only disassemble in an emergency just to get back on the road if I don't have replacement parts handy. Do not do this if you have not worked on brakes before and are very familiar with the systems and have the proper tools however.
If you know what you are doing and have the tools to compress the piston again you can have an assistant VERY CAREFULLY AND SLOWLY press the brake pedal and watch the piston extend from the bore to see if you see any falter as it comes out. If it hangs at any point you can either replace the caliper or disassemble it, inspect it for scoring and clean it up. It is a lot easier just to replace it. I only disassemble in an emergency just to get back on the road if I don't have replacement parts handy. Do not do this if you have not worked on brakes before and are very familiar with the systems and have the proper tools however.
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2004 CLK 500 with AMG Package, Not Convertible
Thanks man, for japanese cars either C clamp is used or another tool is used to compress the piston.
Not sure about Mercedes, since this is my first one. I think, I need to pull left rear pads apart and inspect sliders/pins etc...
Any input or helpful link about doing the job?
Not sure about Mercedes, since this is my first one. I think, I need to pull left rear pads apart and inspect sliders/pins etc...
Any input or helpful link about doing the job?
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2004 CLK 500 with AMG Package, Not Convertible
Is there a DIY video or images for it? What lube should be used for the pins?
As always, thanks
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Actually, just remove the road wheel, then use screwdrivers (or other wedges) to push the pads against pistons, wedged against the edge of the rotors. You have to push both pads simultaneously.
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2004 CLK 500 with AMG Package, Not Convertible
Understand, should I use high temp grease for lubing he pins or mercedes have something specific?
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Maybe an idea too is taking a high pressure washer and spraying into the brakes to clean out possible debris that are stuck in there? Just looks to me that there is a lot of debris that is scrapping onto the rotor. Just an option to try out.
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The ring of rust must be reduced or removed, chances are that the inner rust ring is larger and could have a spot where the rust has fallen of, this would be the thud.
Mercedes as other cars also do is the brake pad does not touch right out to the outer edge of the rotor and the rust keeps the pad from providing parallel contact. The rust will also cause the scoring you see as it is oxidized steel. Inner rotor face is also seen to be totally different in most cases, probably from the processing of the rotor in the first place. Clean the rust with a 4 inch hand grinder, also check for a lip on the inner rotor face, rust also causes issues here.
Mercedes as other cars also do is the brake pad does not touch right out to the outer edge of the rotor and the rust keeps the pad from providing parallel contact. The rust will also cause the scoring you see as it is oxidized steel. Inner rotor face is also seen to be totally different in most cases, probably from the processing of the rotor in the first place. Clean the rust with a 4 inch hand grinder, also check for a lip on the inner rotor face, rust also causes issues here.
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2004 CLK 500 with AMG Package, Not Convertible
I think, am leaning towards rust and debris collected in the brake caliper area.
As pads have a lot of meat of them. I am going to first clean the caliper/pads area thoroughly with brake parts cleaner and water.
If problem won't be solved, going to pull the rotors off and grind them with sandpaper.
As pads have a lot of meat of them. I am going to first clean the caliper/pads area thoroughly with brake parts cleaner and water.
If problem won't be solved, going to pull the rotors off and grind them with sandpaper.
