I do not wash anything bigger than a lap quilt in a regular washing machine. Before I got a front loader, I went to the laundromat and used the large, commercial washer because the action of the agitator in a top loader is very stressful for the seams. I also prefer to dry them in a dryer because unless you have room to lay it flat, the weight of the quilt will cause distortion and stress the seams.
The color catcher is a laundry product that looks like a dryer sheet, but you put it in the washer to catch the dye that runs. They are sold by the laundry detergent at our local grocery store.