96 Legacy Brake Shims Question

[bendecker]

As long as I've had my '96 Legacy (purchased used), it's had two sets of brake shims between the pads and calipers.

 

I've looked all over the web and can't find any picture of a brake shim that looks like the the bigger one that's sandwiched between the caliper and the standard shim that comes with new aftermarket pads.

 

The shims, separate and sandwiched:

 

 

 

 

 

The bigger shims are starting to look pretty beat up and the more I think about it, the more I think they're not needed.

 

Any gurus out there that can shed some light on this? Should I chuck them and call it a day? Or, do they serve some greater purpose than the shims that come with a replacement set?

 

Thank you,

 

-Ben

Edited January 28, 2011 by bendecker

[SchwarzeEwigkt]

Shims often serve an anti-rattle or anti-squeal role. My BMW came with shims and no anti-squeal compound and if you take them shims off and don't put some of that goop on, they'll sing. I ruined the shims on my 97 OBW during a brake job long ago and haven't replaced them, though I always put anti-squeal compound on when I replace the pads. It's done me fine through three sets of brakes with no issues I've noticed.

[tcspeer]

I have a postal subaru (they wear brakes out much faster) that has been on a rt. since 1996, it is a 1997 model. I have many years and pads ago done away with the shims.

 

In fact if you will get the wagner thermo quite pads they have a backing coating on them, and they give instrictions not to use anything else on them as it would reduce the quailty of the noise reducer.

Edited January 28, 2011 by tcspeer

[Rooster2]

It has been my experience that the shims are only there to prevent squeal when the brakes are applied. When I buy new brake pads, there are usually shims included in the box with the pads.

 

The new shims don't necessarily look the same as the ones currently on the car. My guess is that each pad manufacture has their own slightly different pad design. All different shim designs will work just fine. It is not a high tech item that has to duplicate exactly what you see on your car.

 

I have also used the tube of rubberized cream that is made to replace shims. It is applied to the back side of brake pads. The cream functions as a replacement for shims, and works well. However, I don't like using the stuff because I create a gooey mess by the time the job is done. Maybe I am using too much of the stuff. At next pad replacement, I have to use a knife to cut the old hardened cream off.

[bendecker]

Thanks for the replies. I couldn't see any downside to pitching them, but I appreciate hearing others say the same thing before they hit the round file. I'm going to finish up putting the pads in this afternoon and we'll be back on the road.

 

-Ben

[Durania]

I left them off of my Legacy. Got tired of fighting with those stupid things falling off and making it difficult getting the caliper back on around the pads.

[rverdoold]

As said shims reduce rattling. I have 1 on the out side of the brake clamp (housing) and 2 on the inner side at the piston. The shims close to the brake pad usually are coated with a high-temp resistant rubber-ish coating. The reason for the coating is to reduce the rattling. How?

 

Well at the moment the brake is applied the disc and pad heat up very rapid, the heat is transferred to the piston and the brake clamp. The heat makes the metal expand. From the moment the brake is released the disk and the pad are the first to cool down shrinking the metal. The clamp and calliper cool down somewhat later. The rubber backing of the shim overcome the small space that appeared due to the quicker shrinking of the brake pad. The reason there is a second metal shim on the calliper side is to have the piston equally pushing the brake pad.

Removing shims will eventually result in rattling because there is no rubber-ish side to avoid that.

 

I usually put a thin layer of copper grease between the shim and the pad and then some on the clamp and piston, but only on the places where contact with the pad is made.

[Manarius]

Pfft, who puts shims or anti-noise grease on. I've replaced many brake pads at this point and the presence of shims/anti-noise grease or lack thereof has been irrelevant to brake noise. If I have shims, I use them. If I don't, then I don't. I'll never buy that stupid grease though. Wasted money as far as I'm concerned.