Quote:
Originally Posted by wimorrison
Thanks for this. I will have a look at this when I swap the tyres at the end of the month for the winter wheels - something I guess that doesn't happen in your part of the world 
It would still be useful to know what the Volvo specified minimum thickness is as it is tarting to appear that it is almost automatic for Volvo to say that the discs need renewing when a service is done.
I have even been told that you will fail MOT if the discs need renewing, which is strange as they are not measured as part of the MOT, and the starting thickness is different for every car  |
Firstly the only MOT criteria regarding failing a brake discs are :
"a brake disc or drum in such a condition that it is seriously weakened or insecure" mainly all it has to do is pass the retardation test on the MOT ....
Secondly , it is general with volvo that the max wear is 1mm per face , on an XC60 this would make the minimum thickness 20mm on vented rear discs or 9 mm on solid rear discs .
Rear discs are wearing more than fronts , as there is a lot more braking going on at the rear these days compared to the old V70's 900's etc , mainly due to Electronic control going on , ie hard braking and rears do a lot less work , gentle braking and the rears do a lot of work . You also have DSTC which operates the brakes independantly of the pedal sometimes . So the brake life is now determined by how the user drives . Remember you can go 100000 miles and need never touch the brake depending on how you drive and where you drive to !
In general terms you should be able to get through 2 sets of pads per disc as long as you change the first set before they go much below 4mm .