If you didn't get the front-brake squeal TSB done while your car was under warranty you are in for a rude surprise. When the time comes to replace the front disk pads (04465-52210) you will also have to buy a shim kit (04945-52060) for about $30 extra. The old shims will not work with the new pads.

[Note to self: Get all TSBs done, whether I experience the problem or not so I won't have to pay for them later on!]

Anyway, now I have the brakes apart and a completely different set of eight shims in front of me in a disassembled condition. The exploded diagrams in the manual doesn't do me much good, since they depict the old-style shims. If I had a newer manual to look at it would probably show them, but I don't and I can't find one online.

Ok, what to do? Apply a bit of logic. There are two sets of identical parts, so separate them for left and right.

Two of the shims have slots. They go next to the pads. The other two go outside the slotted shims.

Now, which shims go on which pad? Toyota gave a bit of a clue, because one pad has a little spring tab on it. If you try to install the wrong shims on this pad they interfere with the rivet that secures this spring tab.

Now, the pads do come in left and rights, so make sure that you match the pads you are removing with the ones you are replacing. The differences are subtle so look carefully! The obvious one is the spring tab, but the metal backing plate of one pad also has a slightly different shape on the inner radius.

Put a film of the supplied grease between the backing plate of the pad and the shim, and between the two shims. Don't put any on the outside of the outer shim. The slots serve as a bit of a reservoir for the grease. Keep the grease off of the friction surface!

Hopefully this will help other folks who encounter this puzzle!

 

Do you have any pictures to show the new shims?

 

Nope, they're in the car.

The new shims are considerably different than the old, and the new-style pads have notches in different places than the old to accommodate them. One big difference is that the new shim sets have slotted shims on both sides of the caliper while the original shims had only one slotted shim. The slots also are oriented differently. If you follow my instructions above you'll get them installed right.

 

Hang on, help me understand this a minute. I just changed my front pads and didn't put in any shims. And when I removed the old ones, there were no shims. But after reading this post, I looked in my Factory Service Manual, and sure enough it shows shims. My 06 xB has 33,000 miles on it. So what do I need to do? Thanks in advance!!!

Well, I just went down to the garage and looked at the old pads again and sure enough the shims are on them. So I can re-use these on the new pads? Also I have noticed a chirping sound from the front brakes, would this be the cause? Thanks again!!

 

By '06 they had already changed to the revised shims and pads, so all you have to do is pull the caliper off and put the old shims on the new pads. Don't take them apart until you have all the parts in one place so you can just switch the shims from like to like. Don't forget to put a thin film of disk brake grease on both sides of the slotted shim nearest the pad. The shims are there to prevent screeches from the pads.

 

"The shims are there to prevent screeches from the pads."
So this is probably my chriping I'm hearing now? It stops when I apply the brake ever so slightly!!!

 

Probably. The screeches are just the pads vibrating around in the caliper. The shims damp out the vibrations. On the old shims I can see metal-to-metal galling where they didn't do a good job and allowed the pads to vibrate.

I can't speak to how good the new shims are because I've only about 50 miles on newly-turned rotors. The old setup didn't make all that much noise, though it did give forth with a rather disturbing "graunch" now and then when applying brakes at slow speed.

I did the brakes with 1.5mm remaining on the thinnest pad, so there wasn't any opportunity for anything really bad to happen. The brakes were pulsing a bit which is why I had the rotors turned, and the turning seems to have fixed that concern.

53,000 miles isn't bad pad life. The rear shoes still have plenty of friction material left and may well go 100,000 miles. The rear brakes don't really do all that much on an xB!

 

I changed my pads at 80,000 miles, and still had plenty of material. I reused the shims and added some anti-squeel that came in a pouch when I replaced them.

 

Now that I did the job the hard way, I find the exact info on how to do it:

http://tijil.org/Scion_TSBs/br00704r.pdf

 

I would think that most replacement pads I've seen lately already have a shim mounted to the backside of the pads. Just drop them in and go. I wouldn't buy pads that don't have em.

 

Then you won't buy pads from Toyota. The shims come separately.

 

OH ok, wasn't planning to buy Toyota pads so I should be ok.