but my rotors show little signs of wear. Is it safe to assume I just need new rear pads?

 

Grinding brakes strongly suggest at least one brake pad is worn out and the pad backing plate is now in contact with the rotor. If this is the case you’ll be lucky if you don’t have to replace the rotor, and good practice suggests if you change the rotor on one side, you replace the other.
I can’t remember if the rear caliper is a slider, but check the wear rates of all the pads, if there is a big difference then a sticking slider might be the cause, if not a sticking piston.
Better get it looked at soon…
Regards,
White Bear.

 

Thanks Whitebear I am getting it looked at next Monday. The rear rotors definitely have wear, but I certainly wouldn't call it substantial. Based on my experience with my front rotors I would think the rear rotors wouldn't need replacing until they are at twice the "wear" depth then they are now.

 

I think you'll be suprised how little wear these rotors can take. Let us know how you make out!

 

+1

The grinding indicates metal to metal contact. Apart from seriously impairing braking, this will rapidly wreck the disc.

The rear brake on both XK and XKR is ventilated disc (rotor) with an aluminium single acting piston sliding caliper.

The caliper is mounted in a fixed carrier which is secured to the wheel knuckle with two bolts.

When the brake is applied, the piston extends to force the inner pad against the disc. The caliper reacts and slides along two guide pins to force the outer pad into contact with the disc.

Rapid wear of pads is usually caused by the carrier seizing on the guide pins.

Graham