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Of course I didn't put grease on the adhesive side of the shim...  I put it everywhere else that contacted the caliper. The other night i was doing some "more intense" driving and I was getting this horrible squeal from the rears. Not a squeak, a constant squeal until I completely stopped. Maybe they were just too hot but they have never done that before.
99 SVTC, T-Red, #652/2760-12.8.1998
Mother#@%@!* did I sound abstract?
I hope it sounded more confusin than that!
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Hard-core CEG'er
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Originally posted by patman:
This is not entirely true. It all depends on what type of shim is being used or if the pads are being used without a shim. I run a tech dept for a brake manufacturer and own my own brake business as well, this question comes up quite a bit.
There are two basic ways to prevent squeels caused by pad vibration independent of the caliper. One way, which is used by VW, AUDI, and a few other manufacturers is to glue the pad to the caliper. These pads come from the dealer with shims installed on the pad and a paper backing that is peeled off revieling an adhesive during installation. Since the pad is now glued to the caliper, it cannot move independently and therefor will not squeek. Of course this adhesive looses its stick about halfway through the life of the pad and the noise begins. Another way is simply to allow the pad to vibrate slightly independently of the caliper and isolate those vibrations to the pad so they don't reach the caliper. This is done through the use of shims. Grease should only be used on shims that clip onto the pad like those that the japanese manufacturers use. These are generally a two piece shim, one constructed of an antifriction coated mild steel shim and one constructed of stainless steel. Grease should be used between the pad surface and the mild steel shim, and then the stainless shim installed over the top of the mild steel shim, with no grease in between, and then the pads installed into the caliper with no grease between the caliper and stainless shim. But these are fords, not toyotas. The shims found on contour pads are single layer shims that generally have an adhesive to aid in attachment to the pad. The shims that we install on these pads have small taps to prevent the shim from rotating off the pad or dimples punched in them which lock in respective dimples on the plate of the pad so they cannot rotate off the pad. These shims are glued onto the pad and no grease should be used between the pad and shim...cuz then the glue wouldn't stick. Some companies provide a rubberized shim and some provide a steel shim which appears to be painted black. This is an antifriction coating on the shim designed to absorb minor vibrations. The rubberized version works much better which is why more and more OE suppliers are switching to this design. No grease should be used with these style of shims. It is unneccessary and will do little aside from making a mess. Non-adhesive shim (no adhesive between the shim and caliper) allow a slight bit of movement between the pad and shim, and between the shim and caliper. This is sufficient to prevent noise and no grease is necessary. Most brake noise occurs because of poorly machined rotors or rotors that have not been machined, or pads of inferior quality. 
That is quite a nice description of different shims. You are correct in that there are different styles of shims and that the difference is mostly determined by the pad engineers to best match the materials in the pad and the vehicle that it is used on. Generally speaking, the harder the pad material, the greater the need for noise supression help. Part of where this breaks down is that not all engineers are as dilligent (or have cost constraints) as you and I.
I agree that if it is some sort of soft shim or adhesive shim that grease is probably not desirable. Grease would interfear with the design intent of that sort of shim.
I have found, however, that if the shims are plain metal or if there are no shim or if the shim is internal to the backing plate that greasing the backing plate and the shim any place that the caliper touches the backing plate helps to cut noise. Perhaps you are right that it isn't needed in some cases, but my experience shows that it does help.
There are other things that also help. The caliper slide pins (or in some caliper designs the slide grooves) must also be cleaned and properly greased. If it is a floating rotor (not pressed to the hub) it helps to thoroughly clean the mating surface between the hub and rotor and gently apply anti-sieze compound. It helps to gently champher the edges of the pads if they are not made that way. On cars with soft rotors that tend to build up quite a lip on the outside edge of the friction face (best example is Volvo) it helps to champher the edge of the rotor. I'm in the habit of taking a file to the edge of the rotor while it is still turning on the brake lathe after other machining has been done and putting a slight bevel on it. Both inner and outer faces. This helps to cut noise that comes from the lip on the rotor cutting in on the edge of the rotor about mid pad and rotor life wear.
The one thing I can tell you is that I seldom have a come back for noisy breaks, even when I have made the mistake of using crummy pads. I can also tell you that proper lubrication of the appropriate parts in a brake job is the most often neglected part of a brake job and often makes the difference between a lousey brake job and a great brake job.
But then I'm not a brake engineer. I'm a seasoned tech / service manager. My degree is in business management. Maybe I should have taken more tech courses.
Jim Johnson
98 SVT
03 Escape Limited
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Hard-core CEG\'er
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Fu(k shims... I just installed the Ti's and didn't bother. I like HSV. I figure if F1 and MotoGP brakes can squeal... so can mine damnit! (Lets ignore the fact that I forgot to put them on for now shall we?)
Sal Khan
00 SVT - Not pretty
00 Aprilia RSV Mille - Also Loved.
http://www.thelunchjournals.com
"I just want someone I can stand once her mouth is free of obstruction."
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I was going to quote Big Jim but that would get out of hand...kinda long..... so in response to Big Jim, I agree with you 100% when a shimless pad is used that Grease needs to be applied to the backside of the pad. Generally, the only pads out there that don't use shims in this day and age are the midas specials that you get with your $69.99 brake job. These pads are generally crap anyway so who cares if they make noise...you're worried about why your car doesn't stop. I got a little carried away with my last post and forgot to mention this point...just thought I'd throw it in. And I've still got 2 sets of SVT front and rear slotted rotors left and 4 sets of not SVT slotted rotors from my GP that went to hell if anyone is interested. Special clearance prices apply. please email me. Thought I'd slip that in to.
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I contributed to this thread, because I have installed Bendix Titaniums on the front of my Cutlass and my Contour, and because the OEM pad did not have a shim, I did not use any shim on either even though they were included.
I haven't noticed any noise really. Perhaps a little early- morning chatter (before I touch the brake the first time). Certainly no squealing that others here are talking about.
Am I correct to assume that shims are designed to stop noises when my foot is NOT on the pedal? Because whether it's a soft metal or hard metal shim, if my foot is on the brake, the amount of force that ends up pressing the pad against to the rotor has to be equal, even to the non-shimmed car.
So I can see it squelching noise with foot off brake, or during that very initial part of applying the brakes.
I think this is starting to make sense to me now. I'm still not convinced shims are worth it to me. Like mentioned in the long post above, over time any adhesive breaks down. And since the contour shims don't have the tabs around the edges like the honda ones do, the possibility of the shim slipping out and getting lodged somewhere exists, perhaps it's a slim chance.
Brian
99 SVT
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Ah I love it when you guys with OJT experience share your findings! Thank-you! Now I too did the Stazi Rotors and titanium pads about a year ago. Mine is not noise problem but a High speed chatter/vibration under (Interstate speeds) emergency type braking. The harder I push the pedal the stronger the vibration. I used the Shims only and none of the blue anti-squeal goop I have used in the past. I cleaned and polished the slider-pins and used that red synthetic grease from AutoZone. I have used anti-seize in the past and never quite sure which is best. Mainly due the wonderfully salty roads in Ohio. Would it possible be those rubber/polymer bushings (I can't believe the Ford CD does not give it a name?) need replaced? the Caliper piston is not leaking (50K+ miles),but is this a possible cause? I did remove the rotors and the mounting surface was clean, I flushed the surfaces with PB Blaster and applied a light coat of anti-seize. Same for the caliper anchor and re-torqued. Even thing else is fine, it's only when I really lay hard into the brake at speed. It has done it from the being, well I did wait till I had about 100 miles on the new parts before my usual emergency type braking. The self-bedding didn't work or did I do it too soon? One note after a 1000 round trip past Chicago I-80 It seems to have diminished, the vibration? Uneven build up on the pad material on the rotor. Due to budget constraints (early-forced retirement) I can't afford to throw parts at it for troubleshooting/alias self taught!  Oh I have done the fluid flush several times using Castol's LMA Dot 3. Any help or ideas would be greatly appreciated! Thanks Paul
Paul
98 Mystique LS 2ea (07/97)(08/98)
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warped rotors would be my first thought.
Ryan
Trollin!
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Me too, but not brand new ones??? Especially not those fine Autospecialty's. For the life of me I can't figure out what I screwed up/down/sideways???
Thanks
Paul
Oh I use a fine Craftsman clicking torque wrench starting at 60 ft lbs , then 80 ft lbs and finally 100 ftlbs.
I'm not sure all the steps are really nessary?
Got that from former crew-chief in the Air Force.
Paul
98 Mystique LS 2ea (07/97)(08/98)
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Highly doubtful the rotors are warped unless you didn't break them in gently for the first 4-500 miles, or you beat the ever loving crap out of them from the word go. Another bad thing to do with new brakes is ride on them in traffic for an extended period of time, when new, even with light pedal pressure as this heats them up a lot - not good when the pads and rotors are new.
Check to make sure there is not uneven coloring on the rotor surfaces, suggesting possible material buildup. Another thing you want to check is that the spring is installed CORRECTLY - as I had another CEG'er comp[lain about this wehn he had the spring installed incorrectly, thus allowing the caliper to shudder. The spring should go under the finders on either side of the caliper bracket, thus pulling the caliper tight towards the center of the wheel.
2000 SVT Turbo 295hp/269ftlb@12psi
#1 for Bendix Brakes Kits!
Knuckles rebuilt w/new bearings $55
AUSSIE ENDLINKS $70
Gutted pre-cats $80/set
A lack of planning on your part does not constitute an emergency on mine!
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Actually the wife drove it on errands and not hard, hmmmm she does have a bad habit braking medium hard (waiting way too long before she starts slow down) at intersections?
Naw, don't dare even thing about blaming the wife, very treacherous territory!
Thanks Stazi appreciate your time and info! Good luck on the move!
Paul
Paul
98 Mystique LS 2ea (07/97)(08/98)
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