Helm, Inc - GM's "front end" for manuals.
If it has a GM number, you could check with Gmpartsdirect.com.
http://www.helminc.com/helm/product2...1T1XVJV6SS3CT1
2003 H2 Hummer Service Manual (N-Platform)
Price: $135.00
Media: Paper
Language: English
Part #: GMT03N
Models and Years Covered
Contains Factory Authorized Service information written by General Motors. It contains Diagnostic Information and Procedures, Schematics and Routing Diagrams, Component Locator, Repair Instructions, Description and Operation, Specifications, and Special Tools and equipment. Service information on HVAC, Body & Accessories, Restraints, Steering, Suspension, Driveline/Axle, Brakes, Engine and Transmission/Transaxle.
Note: GM Truck Owners, for model years 1996 and prior the service manual is available as a set (or kit) and also sold in sections (electrical & emissions, shop/service manual, unit repair/chassis manual). All three sections are needed for full coverage.
Description:
Instructions And Procedures For Routine Repair Adjustments Maintenance Work Diagnosis/Testing And Removal/Installation Of Parts For Various Vehicle Systems.