he will need a brake tool for the rear brakes to turn the piston in ,its not like the front brakes where you push the piston . also would be a good idea to flush the brake system if its never been done before. and put new fluid in try to use different color fluid so you can tell that you got rid of the old fluid.

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2003 bmw x5 3.0i ,219000km build date 2003-08-18