ka8legend

While replacing the front brake pads on my 88NA, I notice there's an arrow on each shim. Does it have to face up/down when I re-install them, or does it matter? I'm getting tuning fork noise when I hit the brakes. Rotor was resurfaced and brand new United (from Napa) pads were used (as well as the blue "disc quiet" ) and yet I still get noise and a pulsating brake pedal. What gives?

larsyoung

I had the same tale of woe as you are describing. The arrows point in the direction of wheel travel. Are your front brakes single or 4 piston? My 4-piston brakes had 2 shims per side. The more asymmetrical shim went on the outside. Also the shorter pad spring is installed on at the forward direction of the rotor.

Regarding the fun pulsating brake pedal, its definitely out-of-round rotors. I had to take my rotors back to the shop because they didn't machine them properly. For whatever it's worth, Mazda recommends the use on on-vehicle brake lathe.
From the TSB's:
"Mazda's engineers have concluded that the rotor surfaces must be precisely machined to effectively correct brake judder. They also conclude that on-car brake lathes are more precise than off-car brake lathes for machining rotor surfaces. Therefore, an on-car brake lathe is recommended and will be required for all rotor machining done under warranty after January 1, 1995 (see Service Bulletin Category P # 006/94, Issue Date 9/1/94)."
Lars

ka8legend

In the direction of wheel travel? Let's take the driver side; the wheel rotates counter-clockwise, so direction of travel would be down when point of reference is in the 9'oclock position, and pointing up when in the 3'oclock position. So which point of reference should I use? It's a GXL model btw, ie 4piston calibers.

larsyoung

Using the driver's side wheel, lets say the caliper is at 2:00. the arrow should point towards 12:00, or upwards.
First, the shim that looks symmetrical goes on, then the one with the arrow. Another way to look at it is that since the outermost shim, the one with the arrow, is wedge shaped, the fatter side of the wedge goes in the top of the caliper. Also the short spring is placed on the top side of the caliper.
Mine were installed the other way and they made annoying clicking noises every time you touched the brakes.

I hope this helps.

Lars

ka8legend

Thanks again. I'll try it after getting new rotors.