My 2000 Volvo S40 owners manual page 60 Driving Economy mentions dragging brakes. I am starting to hear a slight dragging sound from the rear passenger side during slow speeds only. Can disc brakes really drag? 88k original miles, brakes done at 38k. User serviceable?? Thanks!

 

Yes, the piston in the caliper can stick causing the pads to drag. Check the pads visually. Is one noticeably thinner than the other? Both pads on that wheel should be wearing evenly. If one is thinner then your piston in the caliper could be stuck. If it is there won't be any doubt. You will see it clearly.

Now if you have something like a collapsed brake line causing trapped pressure at the caliper then both pads will be worn evenly but allot thinner than the other rear wheel. Pads are replaced in pairs so all on the rear should be even as all the front should be even.

Calipers are rebuildable although I've never attempted this with my 2001. Most rear calipers with built-in parking brakes are more complicated than I care to tackle. I just buy the reman unit from the parts store and keep the receipt in case it's no good.

If you service the caliper remember to retract the piston by turning it, not by pushing straight in like the fronts. The rear caliper pistons are connected to the parking brake and must be turned to retract them in the caliper bore.

 

Thanks, Bro Hudini. Appreciate the input. Will check it this weekend.

 

The slight noise became alarmingly loud going down a steep grade. Put the s40 up on jacks and inspected rear brakes. No kinked brake lines, plenty of pad left, rotors were cherry. Brushed off the dust, couple shots of penetrating lube on the springs at the rear of the caliper assembly and viola

 

ALWAYS pays to research and look at things before scurrying to a mechanic.

 

Not to thread-jack, Johnny, but I think I'm in the same boat!

When I bought the car, it had been sitting for a while and the parking brakes had stuck onto the rear rotors. I've ordered new pads and rotors, as there is a judder from the rear (pads have left deposits/warped the discs) and when I got a flat tire (damned nail!!) this evening, I went and had a gander at the parking brake section as the parking brake had been flaccid since the beginning - a telltale sign that the parking-brake lever on the caliper has stuck in place.

I'll try your penetrating lube trick this weekend at the garage! Ta for the heads-up!

Liam