Ok. Brake repair lesson 101.........NEVER replace/repair just one side of the brakes. If you needed to replace one disk then you replace both (front or rear) with either new or used disks but they must be the same thickness if they are used (from different cars isn't recommended because the disks could be different material/brand.

If you replace just one caliper then you should rebuild both calipers on the axle so that they are even. Also, if you do replace the caliper then use the brake pads you previously used or new one since the "spare" caliper you install will probably have different brake pads fitted.

You should probably remove both calipers from whichever axle you are working on (front or rear) and send them away to get rebuilt if you aren't confident to do it yourself.

Check the rotors are about the same thickness and the surface condition is similar. If they have a glazed or scored surface then send them off to be machined as well.

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Alex Shevlin (Sydney): '71 142S, '72 144S, '81 244GLE, '81 244GL, '01 V70XC