Where do I put the grease on my disc pads?

[Gebo]

I'm installing front disc brake pads and am putting in OEM shims. There are 3 shims per pad. Two black ones that go directly on the pad and a silver one that goes on the inside on top of the black one. I have the special CRC synthetic Brake and Caliper grease.

Will it hurt to put a little on both sides of all the shims? I know it goes on the outside of the silver shim where the piston presses.

 

[SLCraig]

You should take a pic, I can't say I've ever seen any setup with 3 shims per pad. Are you referring to the ones that get put in the caliper bracket?

Also, no need to grease the back of the pads. I use CRC disc brake caliper quiet (red goo) to stick the pads to the piston and the outside of the caliper.

Grease only the slides and a tad where the pads ride in the shims in the caliper (top and bottom edges)

 

[mechtech2]

Avoid grease or anti squeal sauce on you new pads.
Those 3 shims make anything else you add redundant, and may work against you.

You should use a bit of lube on the edges. I lube the knuckle where they sit, or the little pads they ride against.
And of course clean and lubes sliders/pins are a must!

 

[Gebo]

Originally Posted By: SLCraig
You should take a pic, I can't say I've ever seen any setup with 3 shims per pad. Are you referring to the ones that get put in the caliper bracket?

Also, no need to grease the back of the pads. I use CRC disc brake caliper quiet (red goo) to stick the pads to the piston and the outside of the caliper.

Grease only the slides and a tad where the pads ride in the shims in the caliper (top and bottom edges)


There is a Flat black metal shim that touches the outside of each disc pad. Then there is on additional flat shiny metal shim that goes on top of the black metal shim on the inside pad. This shiny flat metal shim covers the flat black metal shim. The round brake piston makes contact with this shiny shim.

One shim on outside pad and 2 on the inside pad.

 

[mechanicx]

This sounds like a setup common on early japanese brakes. Some of those had 4 shims with and inner and out for both pads. I think they recommend to put thin layer of grease on both the inner and outer shim, but primarily on just the inner shims as I remember it.

 

[SteveSRT8]

I can't tell you how many sets of GM brakes I have installed, but it's a LOT! And nary a one with any sauce anywhere. Just lube the pins and sliding parts.

Be very careful using any lube on the pads. As stated above it must be applied very precisely, as there is a bit of heat involved here!

I would also ask if the factory manual recommends grease at the piston contact point.

 

[doitmyself]

I remember my kid's Escorts came with OEM 3 layer shims to help abate the noisy brakes the early models were claimed to have.

Here's an article that touches on the "theory" why some believe it is good to put a bit of "grease" between the outside pad/shim and caliper contact points: http://www.aa1car.com/library/tr996.htm

Here's my thoughts: The glue like CRC brake pad goops state on the label not to use them on shimmed pads. The theory being that the glue will cause the vibrating shims to be pulled off.....DON'T shoot the messenger....several claim they use the goop on shimmed pads.

The article I linked said to use a high solids moly paste (not grease) as a thin layer between pad and caliper contact points. I have a Ford TSB recommending silicone there.

The whole idea is that IF you have noisy brakes, that tiny layer of lube will mitigate the resonation from vibration.

Believe what you want. While I cannot find my references, I "thought" that I read that you do NOT put grease anywhere except between the outside shim and caliper contact point (none in between the shims)...just a faded memory on this one. IMO, the grease should be paper thin as you don't wanting it to muck things up.

Of course, many put a TINY layer of grease, moly paste, or anti seize on the pad ears.

Again, I'm just parroting stuff I googled....don't shoot the parrot!

Some more from Bendix: http://www.bendixbrakes.com/techCorner/faq.php Brake Lube, not a contradiction....

"Stopping noise with Bendix® Ceramlub™
As brake pads are forced into contact with rapidly-spinning rotors, friction between the
working surfaces induces vibration in the pad assemblies. It’s necessary to absorb that
vibration.
Using a liquid noise suppressor was once a common, noise-control strategy. It is used less
nowadays. Resilient shims are now more common and for several years, many
manufacturers have called for the use of lubricant between pad plates and calipers. Unlike
shims, which typically fit just between the backs of pads and the calipers, lube may also
be used where edges of pad plates touch calipers and their mounts."

 

[brelandt]

Originally Posted By: SteveSRT8
I can't tell you how many sets of GM brakes I have installed, but it's a LOT! And nary a one with any sauce anywhere. Just lube the pins and sliding parts.

Be very careful using any lube on the pads. As stated above it must be applied very precisely, as there is a bit of heat involved here!

I would also ask if the factory manual recommends grease at the piston contact point.


This right there! All the ASE guys in my shop does it this way.

 

[Merkava_4]

The grease is for the caliper slide pins; that's all it's for.

 

[xBa380]

I put the grease on my caliper slide pins, all over the piston face that will contact the back of the brake pad, on the piston seal/boot and the caliper on the opposite side where it contacts the back of the other brake pad.

 

[mechtech2]

If you put grease on the pad or shim where it contacts the piston, it will very quickly go away at that point and the contact is just like nothing was ever used in the first place.
There is nothing wrong with anti squeal sauce - it is just not needed with shims. And if it is left to set up/harden before mashing the pedal, it will not seat right - it will be rubbery.

 

[The Critic]

For shims, you should use Molykote M77 for the metal-to-metal contact. This what Honda requires. It would also be beneficial any other metal-to-metal applications. And no, high quality silicone or synthetic caliper grease will not melt in this application - that is why OEMs recommend it for this use.

 

[mechtech2]

First of all, many shims are coated, and not metal to metal.
The piston will quickly displace any lube put on them, anyway [heat and pressure]. It has nothing to do with any melting.
So you now have a substance sitting on the pad or shim doing absolutely nothing except attracting dirt and brake dust..

 

[The Critic]

Originally Posted By: mechtech2
First of all, many shims are coated, and not metal to metal.
The piston will quickly displace any lube put on them, anyway [heat and pressure]. It has nothing to do with any melting.
So you now have a substance sitting on the pad or shim doing absolutely nothing except attracting dirt and brake dust..


This depends. If you are using a silicone paste, I would agree with you.

However, if Molykote M77 is used, then no. In fact, Honda clearly requires the M77 paste to be used between the pad backing and the coated shim for noise reduction. I have sitting in front of me, a 50k old pair of OE Honda pads that were correctly buttered with M77. The piston did not cut through the dry film of M77 at all, and it is still very noticeable (and was likely quite effective).

 

[SteveSRT8]

As I asked earlier: got anything on paper to back up all this grease? I have some manuals here and they most certainly do not recommend any "grease" on brake parts except for pins and hardware surfaces.

IME any grease will melt if it's directly on the back of a pad. If it didn't that's luck, not skilled assembly. Pad temps are outrageously higher than grease's melting points!

 

[Turk]

Question:

Can White Lithium Grease be on new Caliper bolts, or does it need to be a Silicone Grease?

 

[The Critic]

Originally Posted By: SteveSRT8
As I asked earlier: got anything on paper to back up all this grease? I have some manuals here and they most certainly do not recommend any "grease" on brake parts except for pins and hardware surfaces.

IME any grease will melt if it's directly on the back of a pad. If it didn't that's luck, not skilled assembly. Pad temps are outrageously higher than grease's melting points!

See page 19-12 from this particular Acura TSX factory repair manual; pretty much every Honda has the same set of instructions:

http://www.cyforce.org/tsx/tsx-brakes.pdf

 

[The Critic]

Originally Posted By: tpitcher
Question:

Can White Lithium Grease be on new Caliper bolts, or does it need to be a Silicone Grease?


No, you must use high-temperature silicone paste on the slide pins. Ford makes a great product under the Motorcraft XG-3-A label.

 

[SteveSRT8]

Originally Posted By: The Critic
Originally Posted By: SteveSRT8
As I asked earlier: got anything on paper to back up all this grease? I have some manuals here and they most certainly do not recommend any "grease" on brake parts except for pins and hardware surfaces.

IME any grease will melt if it's directly on the back of a pad. If it didn't that's luck, not skilled assembly. Pad temps are outrageously higher than grease's melting points!

See page 19-12 from this particular Acura TSX factory repair manual; pretty much every Honda has the same set of instructions:

http://www.cyforce.org/tsx/tsx-brakes.pdf




Thanks for the link. I note that it specifically states to use the molykote only on the inner sides of the shims, and not on the outside facing the piston.

 

[mechanicx]

I don't normally put grease on pad anchor clips (retainers) or on pad shims. But Honda does recommend M-77 applied to all sides of pad shims ("to the other areas indicated by arrows" ie piston and outside of the outer pad shim), pad ears and the backside of pad retainers. Also most service info I've seen says to apply thin layer of grease (usually silicone but Honda recommends M-77) to outside areas of pad shims for noise reduction. Some of the high temperature brake grease even silicone is rated to 2000 F.