Product review (5 stars): Rolls Like New!
These saved a trip from the appliance repair person!  Although we only had one that was broken, the other three felt like they were also corroding (which should not be a surprise) and therefore I ordered four.  Once I got them on the tray slides like new.  I would also recommend that you take out the upper tray before attempting to replace the rear rollers.  The rollers are not that hard to put on, but it does take a bit of twisting to get them on right, just be patient and do not use too much force, as you do not need to!