Why do my rear disks look like this?

[babak]

I have vertical lines on my rear disks on both sides (left is worse than right). The fronts are fine as I recently had them changed.

Is this something I need to worry about?

 

[vile]

Sticking caliper and your brakes has got hot.
I think you need to take the wheels off and inspect.

 

[Jon_G]

***uming that you have a saloon, I think it's just where your pads are sticking on very slightly when you park up. But, to be safe, check that neither the caliper nor the disks are getting hot after a run (try not to brake during the test, if possible!).

Just to confirm, is it a tourer or a saloon?

 

[babak]

Its a saloon and I haven't noticed my wheels/discs to be getting overly hot but ill make a point of checking when I get home today.

 

[barneyrubble]

looks like the lower edge of the pad is leaving an impression on the disc so maybe there is some dirt trapped in there.

don't think new discs and pads would hurt to be honest, or at minimum a disassembly cleanup and lubeup

 

[barneyrubble]

if you have a micrometer or borrow one you can check the disc thickness - if it's less than 8mm it needs replacing.

 

[93 accord]

Looks worn from here, notice the outer lip. Get new, but before you do that, do as advised above mentioned, check to see if there is an underlying issue with the caliper. Simple jack the corner up, and (handbrake off) spin the wheel, is it free? Yes, excellent, go get some new discs. Spin the wheel, it turns but stiff, or hard to move, theres a further issue.

 

[Blanco808]

I ***ume your talking about the dark lines that are quite difficult to make out from the photos. They almost look like fractures, are they deep? Either way they don't look too good i would get them changed quickly for the sake of £40 - 50 before you do any serious damage mate