REAR PAD RENEWAL

1

With the car on axle stands, take off the road wheels and calipers. Access to the pads is via two bolts. Lock them with a 17mm spanner and remove as shown.

2

Once the bolts are out, pull the caliper up and off, then support it out of the way with the usual metal shirt hanger.

3

Wiggle the pads out sideways from the caliper bracket, leaving the stainless steel shims in place.

4

There’s no corrosion on the wheel hub, which makes a pleasant change. A light spray of oil protects against further rusting.

5

The inner pads were worn more than the outers, indicating a lack of equal movement within the outer and inner caliper slides. The new pad (left) had nice chamfers and surprisingly little material thickness, bearing in mind that the MX-5’S weight distribution means that these rears are worked harder than with the majority of cars. There is plenty of caliper slider room for about double the material thickness.

6

The inner pad shows more loading due to slightly less ease of movement on the outer’s stainless steel slides here, so we greased them. The inner is just over the legal minimum of 1.5mm.

7

There’s no need for grease on the back plate of the pads due to the plastic anti-rust and noise-coating. Shown is the piston backing plate of the old pads, where a light smear on the caliper contact points keep them clean.

8

The worn inner edge clearly shows the change in friction material that generates the rasping warning sound.

9

The caliper piston is a screw-in-while-pushing-back into the caliper body, but the grooves still have to be aligned as shown to locate into the pad’s dimple.

10

Put a dab of copper grease on the backplate locator and stainless steel insert on the caliper bracket – this had been lacking here. New parts are available.