Sierra 2500 4WD V8-6.6L DSL Turbo (2007)
6. If brake fluid is to be added to the master cylinder reservoir, clean the outside of the reservoir on and around the reservoir cap prior to removing
the cap and diaphragm. Use only Delco Supreme 11(R), GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a
clean, sealed brake fluid container.