Uneven Brake Pad Contact

[magnuz]

It's quite a common problem on most cars with discs on the rear.
The rear brakes don't really need to work hard & often get a build up of rust on the disc.
To help keep the rear brake discs clean i regularly pull the handbrake on slightly when going down steep hills !

[jcwacky]

Just to update, the local garage took a look and decided it's due to the discs/pads corroding due to their age, and just recommended I get both the discs and pads replaced before the next MOT.

[pierremcalpine]

Bah - no need for that. Just apply the brakes moderately a few times until they are shiney again. If that doesn't work you have a different issue.

[shanegtr]

Here in Australia the only brake rotors I ever see looking that bad are normally on boat trailers. If it was mine I'd be putting new rotors and pads in

[skyship007]

Originally Posted by jcwacky

Just to update, the local garage took a look and decided it's due to the discs/pads corroding due to their age, and just recommended I get both the discs and pads replaced before the next MOT.

How old (Miles & years) are the discs ??

Did you use OEM certified standard quality brake pads and service the sliders, pins et al ??

The V40 does tend to wear out or corrode back brakes (Including calipers) slightly faster than some other cars of the same era. The reason is that although they used high quality brake parts, the air flow pattern around the rear axle of longer estate cars, does result in more salty spray around the stern section, hence faster corrosion. The splash guards also corrode fairly quality due to too thin a Zinc coating.
My back brake pads wore out before my fronts (All new front and rear Volvo parts fitted at the same time after purchase) and the disc wear was enough to indicate that the discs are only good for 2 sets of pads, so the discs were not changed. The wear on the front discs was minimal.

IT'S VERY IMPORTANT THAT THE BACK BREAKING SYSTEM IS IN REAL GOOD CONDITION (INCLUDING THE CALIPERS), COS THE ABS SYSTEM WILL NOT ALLOW MAX FRONT BRAKE PRESSURE IF THE REAR BRAKES WILL NOT REACH A POTENTIAL LOCK UP. So if only one of the rear discs can't be slowed down correctly (Intermittent full lock), the resulting braking distance performance can be dramatically worse.

If you are short of dosh, just drive slowly along a road that is not too busy whilst pulling the handbrake. KEEP THE BUTTON PRESSED IN AND BE CAREFUL YOU DON'T DO A HANDBRAKE TURN BY MISTAKE !!
That might clean up the discs.