Bosch quiet cast brakes not so quiet - PeachParts Mercedes-Benz Forum

otto huber · #1 10-12-2014, 01:26 PM

I installed some Bosch quiet cast brakes on the rear wheels of my SD a few weeks ago, and they were still consistently squeaking up until yesterday. I cleaned off the grease that they supplied with the pads, and smeared anti-seize on them. The brakes are now quiet, so if you get those Bosch pads, throw out the grease that they include with them.

leathermang · #2 10-12-2014, 03:04 PM

So you are talking about on the back of the disc brake pads?
Any grease included with them was likely for the rods on which the calipers float...
and something like Permatex 80077 Disc Brake Quiet would be used on the back side of the actual pads...

sleepstar · #3 10-12-2014, 03:37 PM

the paste included with them should be applied to the back and sides of the pads. all surfaces except the friction surface. i don't know if i've ever used the included paste though, i usually use MB grease .

otto huber · #4 10-12-2014, 05:21 PM

Quote:

Originally Posted by leathermang

So you are talking about on the back of the disc brake pads?
Any grease included with them was likely for the rods on which the calipers float...
and something like Permatex 80077 Disc Brake Quiet would be used on the back side of the actual pads...

Yes, I tried both the Bosch grease and the anti-seize on the back side of the pads. Anti-seize is the way to go.

leathermang · #5 10-12-2014, 05:49 PM

Normal anti seize compound may not have enough ' body' to function properly as a sound deadener ...... so for others I suggest using the well known product made by Permatex..

mannys9130 · #6 10-12-2014, 10:57 PM

If the pads have anti-noise shims, you install them DRY with nothing on the back. You lube the sliding surfaces where the pads ride in the caliper bracket, as well as the slide pons themselves. Clean the rotor thoroughly before installing, and make sure not to contaminate the pad or rotor surface. A pad with anti-squeal shims is made noisy when goop is put on the shim.

leathermang · #7 10-13-2014, 02:43 PM

Yes, if you have the shims... dry....
if you just have the pads... then some kind of dampening ' paint' on the back can help.

mannys9130 · #8 10-13-2014, 05:01 PM

Look at the Bosch QuietCast pad. Here is the website for that specific product line as well for reference. QuietCast

These pads should not have ANYTHING smeared on the back. That shim does anything and everything required to stop squealing. The engineers spent lots of time and money to develop a proprietary shim. To blame the pad for improper installation isn't fair. That's on the driver/tech for not following proper protocol.

Most pads today have anti-noise shims attached as standard. While I'm sure you could find pads with bare backing plate, they'd probably be some mean Chinese wares for sure... I'm not sure I'd want something that cheap and basic on my daily driver vehicle.

otto huber · #9 10-13-2014, 05:15 PM

Quote:

Originally Posted by mannys9130

Look at the Bosch QuietCast pad. Here is the website for that specific product line as well for reference. QuietCast

These pads should not have ANYTHING smeared on the back. That shim does anything and everything required to stop squealing. The engineers spent lots of time and money to develop a proprietary shim. To blame the pad for improper installation isn't fair. That's on the driver/tech for not following proper protocol.

Most pads today have anti-noise shims attached as standard. While I'm sure you could find pads with bare backing plate, they'd probably be some mean Chinese wares for sure... I'm not sure I'd want something that cheap and basic on my daily driver vehicle.

I stand corrected.

tyl604 · #10 10-13-2014, 05:16 PM

I am not sure you guys are correct about the shims for normal, run of the mill brake pads. I have had shims on my 300SD since 1981. Every time I change the brake pads I spray the blue sound deadener on the back of the brake pad, let it dry for five minutes per directions on the spray can and then stick the shim to it. Have never had a problem with squealing brake pads except one time when I purchased some cheap ones from Pep Boys.

Where do you get info that you are not supposed to spray anything on if you have shims?

I just went out to the garage and looked on the can of CRC Disc Brake Quiet. Directions say to spray the backs only of the pads and let dry for five minutes before installing them. It conveniently says nothing about what to do if you have shims. No idea about the Quiet Cast pads; do the directions tell what to do???

mannys9130 · #11 10-13-2014, 05:34 PM

Quote:

Originally Posted by tyl604

I am not sure you guys are correct about the shims for normal, run of the mill brake pads. I have had shims on my 300SD since 1981. Every time I change the brake pads I spray the blue sound deadener on the back of the brake pad, let it dry for five minutes per directions on the spray can and then stick the shim to it. Have never had a problem with squealing brake pads except one time when I purchased some cheap ones from Pep Boys.

Where do you get info that you are not supposed to spray anything on if you have shims?

I just went out to the garage and looked on the can of CRC Disc Brake Quiet. Directions say to spray the backs only of the pads and let dry for five minutes before installing them. It conveniently says nothing about what to do if you have shims. No idea about the Quiet Cast pads; do the directions tell what to do???

05016 - Disc Brake Quiet, 4 Fl Oz

Look at that and read the first paragraph. The last line says...

"For use on the back of non-shimmed disc pads."

tyl604 · #12 10-13-2014, 05:43 PM

Both my cans of CRC Disc Brake Quiet are different from yours. Mine are in spray cans and they do not say anyplace on the cans that they are for disc pads without shims.

Must be a different formulation.

mannys9130 · #13 10-14-2014, 12:12 AM

Ultimately, you'll do whatever you want to do. You asked where it says not to use on shimmed pads. I showed you. If you have an old can of product with old text, you won't see the revised literature printed on it. If it gives you peace of mind, goop it up. Just know it isn't the right way to do the job. Shimmed pads = dry installation At best, you're wasting money on unneeded redundancy. At worst you're compromising the shim and destroying its ability to keep the pad from vibrating between the caliper and rotor. Though the argument technique is a fallacy, I've done countless brake jobs through the course of my work and I have not had a single come-back regarding a noise complaint. I'm not saying "I've dkne it this way for a while, and haven't had issues so it must be the right way." I'm saying "I've done it the right way for a while and as a result I don't have any returning customers presenting me with problems." That's why it isn't a fallacy.

uberwasser · #14 10-14-2014, 12:16 AM

Good points Manny. To be fair though, the Textar's I installed on my '79 last year were not equipped with shims and I'd say they are better than Chinese bargain bin brands.

tyl604 · #15 10-14-2014, 01:07 PM

Manny - you might be right.