Broken wheels on lower rack

This problem was making me NUTS! Every time I pulled the lower rack out, the rack would go off the track, threatening to break every dish, and I would literally have to half-carry the rack to move it in and out. VERY frustrating. No money for a new dishwasher, didn't want to pay for a whole new lower rack ($100). Then I discovered I could simply replace the wheel assemblies for less than $30 and no toold required. Yee-hah! It was literally a SNAP!