Just changed rear rotors and pads on all four wheels. Thankfully it seems to have resolved the shuddering vibrations that it had when braking before.
It did not however change the light scraping sound coming from the driver side wheel. It sounds and feels as if the pads are always lightly rubbing, when the brakes are not applied. It's like the brakes are not releasing completely. Strangely, the sound is the same with the new pads as with the old ones. I thought the old pads were causing it. What could it be?
During the jobs I did come to find that my axle on that side also needs replacing. The boot looks fairly done. I guess that's my next task.
Could the worn axle be causing the rotors to rub on the pads?
For a moment I though wheel bearing, but most of the sounds I've heard described were a low vibration, not a "light scraping sound"
ANY helpful suggestions would be greatly appreciated. Thnx!

 

Front or rear?

 

Did the rear rotors spin freely? Could be a bearing. Also, if you have a bad caliper, it would cause pads to rub. Were any pads worn unevenly?

 

Yes the pads were worn unevenly.
After another day of study I have determined the sound to be coming from the ds rear wheel. Parking brake shoes rubbing a little maybe?
THe sound (a light scraping) seems like the rotor is grazing the dust shield but when inspected it seemed solidly in the right position.
I also fiddled with the clips that hold the rear brake pad pins, but that didn't seem to change it either.
I adjusted the parking brake shoes all the way in and tightened up the lever.
It did seem to reduce the sound a bit, but the e-break does not hold as well on that side now. THat would be fine with me if the sound vanished, but no such luck.
Any ideas? Thanks

 

I would take the dust shield off. Run it for a day without it. Also, which shoes were worn more than others?

 

Before removing the dust shield which seems like a bit of a task, I tried putting the rotor back on without the parking brake shoes. THe sound was no more. It seems that the parking brake shoe assembly is not seating just right thus causing a little rub even when adjusted all the way in. The leverage mechanism that causes them to expand flops around pretty loosely and the whole assembly can move to either side and up and down. When the wheel is on, with the shoes on, I can hear it move to on side or the other when I change spin directions.

 

I was wrong. After trying taking off the e-brake shoes, the sound was still there once I put the brake caliper back on. It seems that the caliper is sticking a bit, which I've read is common with the 850.
To answer an earlier question. I did not take note of which pads were more worn. I just know they were uneven. I figured it would be resolved by new rotors and pads. I see now that it may have helped me see which caliper piston was hanging up.
I guess for now I just have to tolerate the "light scraping" sound until I can afford a new caliper. My $ are already tied up in fixing the left drive axle and the ball joint.
Thanks again for the knowledge.

 

Did you use OEM parts?

 

My pads are not, but the new rear rotors are.

 

Brake calipers stick on all kinds of cars. I think it's because people don't bleed their brakes that often and air gets in there. Then dirt or moisture can get in and cause mild corrosion, then they fail. I have heard of people rebuilding them or you can get a used one for something like $25.

 

Check and make sure the spring is seated all the way on the pins. If it is not then the spring will just lightly touch the outside edge of the rotor. That will cause the noise you hear.

 

What site do think is good for ordering used parts. Looking on Ebay I couldn't find the left rear caliper for under $130.
Do you know anything about buying rebuilt and/or rebuilding the left drive axle. It seem that there must be more to it than just the boot replacement kit. Rebuilding it seems like a better bet for me than buying a new one that is of good enough quality.... having more time than money right now.
I am also interested in rebuilding my ball joint on that side.