I would pull the drums. You may have a leaking wheel cylinder or just a lot of dust in the drums. It is also possible the linings are glazed. If the wheel cylinders have contaminated the brake linings replace the brake shoes.
A forum community dedicated to Dodge Cummins Diesel truck owners and enthusiasts. Come join the discussion about reviews, drivetrain swaps, turbos, modifications, classifieds, builds, troubleshooting, maintenance, and more!