AppliancePartsPros.com sells a nice, complete 4-piece Roller & Stud Assembly replacement kit (WD12X10327) that is a simple and cost-effective solution for this issue. The design of the dishwasher rack of appliances from this era was brilliant in my opinion. Online I saw you only need a quarter-sized coin to twist and release the side rail end caps, pull out the rack, unsnap/slide off the old connectors and slide on/snap in the new ones, then replace the rack and end caps to complete the job. No tools, ten minutes. Great design and a nice parts kit. Amazing.