Spoon Sports 11/4/2011"And I can't tell where the grinding is coming from." - Based on this statement of yours, its safe to assume its not really coming from the brakes. I mean i cant hear it obviously but ill take your word for it.
This can be a bit far fetched but this happened to my friend. He spent $1000 to find out what it wasn't. Wasn't CV joint, wasn't axle, wasn't hub bearing. What it was was a simple plastic clip that holds shifter cable away from the drive shaft had popped out of hole in flange on transmission driver sider allowing cable to contact driveshaft on bumps, turns to right, moderate braking. Also check that the other shifter cable isn't wedged between transmission and mount i believe it was. You can tie the cable up with a 5 cent tie lock. Good Luck