John P Denver , CO January 23, 2016 Appliance: Frigidaire Dishwasher MDB122RFS1 Frigidaire Dishwasher Mdb122rfs1: Top rack of dishwasher had several rusting tines and bars. How to replace Dishwasher Upper Rack Assembly. Replaced the rack. Though the new rack is about 3 inches deeper (or taller) than the old rack, it fit easily into the dishwasher and works great. Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes