Brake pad shims

Status
Not open for further replies.
My point is that brake grease is not a sound absorbing/dampening silastic material, like the stuff made for brake anti squealing is.

Over the years, I have had good success with the red anti squeal sauce,and various lubes have not worked well for noise reduction.

I don't use sauce on pads with shims, unless there is a rare problem.
 
Originally Posted By: mechtech2
My point is that brake grease is not a sound absorbing/dampening silastic material, like the stuff made for brake anti squealing is.


The rubbery stuff does not dampen or absorb sound. It simply prevents squeaking from occurring in the first place by dampening the transfer of harmonic vibration that causes the noise in the first place. Grease will do the same thing, probably to a lesser extent. Specifically speaking, on my car neither method results in more or less squeak (none to speak of).
 
5 personal observations to share:

(1)If the original (OE) pads came with shims, then most likely you may have to go with shims for aftermarket replacement pads to keep your brakes from vibration (engineers for your particular car may already have factored the vibration part into the braking system, thus the shims part)

(2)If your car originally comes with shims but you remove it and decided to put brake squeal or some secret high-temp "sauce" on it, chances are, you'll get 50/50 chance of getting squeally brakes again due to vibrations imposed onto the braking system during use.

(3)If your brake pad friction material belongs to those "hard, squeally" type, nothing can stop it from squealling (sooner or later, it will come back to haunt you again)

(4) not all brake pads are created equal, for I discovered this some time ago that certain brake pad materials/brands will not squeal as much as, say some others. Also: semi-metallic has a higher tendency to squeal than, say , organic or ceramic type (general observations, specifics omitted).

(5)IF your rotor(s) out of true even just a slight bit, most likely it will squeal no matter how hard you try to use(sauce, rubber anti-squeal, etc.) and the only way to overcome this is to true the rotors and then carefully follow the proper break-in procedure all over again to embed the pads to the rotors. Unfortunatly, not all brake rotor machining are created equally and most general/aftermarket machines that are30+ yrs old cannot create the kind of proper machined texture to properly facilitate modern brake pad materials to embed, esp. certain semi-metallic compounds. I found this the hard way after trying numerous of machines in my neighbourhood and also new rotors from Aimco, Raybestos, Japanese OE, Brembos, unidentified chinese casts, etc. and not all of them can break in the pads properly, and at the end it will squeal in about 3000~8000kms.

Q.
 
Also: one shall seriously considers the following:

(1) all braking systems will vibrate, and the vibrations, depending on the speed of rotation, materials used, etc. will vibrate on different frequencies. The harder the friction materials used, the higher the pitch it will be.

(2)rotor surface texture, uneven-ness, and brake pad mating surface will ultimately governs the vibration and it's intensity.

(3)most recently released special brake pad backing secret sauce will help in dealing with these squealing somewhat, if you know how to apply them to your situation.

(4)brake pad backing shims actually helps in shifting the vibration point (resonating point) away from the original (when it creates the most vibration), so as to dampen the braking systems. Eliminating them and perhaps substituting them with something else is generally not a good idea.

My 2'cs worth.

Afterall: I hate doing brakes after so many years.



Q.
grin2.gif
 
Originally Posted By: Quest
(5)IF your rotor(s) out of true even just a slight bit, most likely it will squeal no matter how hard you try to use(sauce, rubber anti-squeal, etc.) and the only way to overcome this is to true the rotors and then carefully follow the proper break-in procedure all over again to embed the pads to the rotors. Unfortunatly, not all brake rotor machining are created equally and most general/aftermarket machines that are30+ yrs old cannot create the kind of proper machined texture to properly facilitate modern brake pad materials to embed, esp. certain semi-metallic compounds. I found this the hard way after trying numerous of machines in my neighbourhood and also new rotors from Aimco, Raybestos, Japanese OE, Brembos, unidentified chinese casts, etc. and not all of them can break in the pads properly, and at the end it will squeal in about 3000~8000kms.

Q.


I always check runout and I never have rotors machined. I always install new pads and new rotors at the same time, because they happen to wear out at the same time. That's another advantage of not mixing and matching rotors and pads from different manufacturers. I've never had a squeal issue besides an rare chirp. I have never had a car that used shims on the pads. I don't know about my Buick and Chevy, because I took those junkers to Sears instead of getting my own hands dirty.
wink.gif
 
That rubbery stuff most certainly absorbs vibrations. It is not a glue.
A similar substance was used on the back of some golf club irons to attenuate perceived vibration and impact feel.
 
Status
Not open for further replies.
Back
Top Bottom