2004 GMC Envoy Owner's Manual - Page 425

Additional Required Services (cont'd) Service and Miles (Kilometers) Change automatic transmission fluid and filter (normal service). Automatic transfer case only: Change transfer case fluid. See footnote (g). Replace spark plugs. An Emission Control Service. V8 engine only: Inspect spark plug wires. An Emission Control Service. Engine cooling system service (or every 5 years, whichever occurs first). An Emission Control Service. See footnote (i). Inspect engine accessory drive belt. An Emission Control Service. • 25,000 (41 500) 50,000 (83 000) 75,000 (125 000) 100,000 (166 000 125,000 (207 500) 150,000 (240 000) • • 6-7