RepairPal Certified shops can diagnose and repair your 2000 Chevrolet K2500. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
What is the source of the new pump? Did you purchase it from a Chevrolet dealership? The pump could be definitely a problem.
What was the purpose of replacing the pump? Was there no power steering operation before you replaced the pump? Or was it leaking?