2009 Hummer H3T Owner's Manual - Page 233
2009 Hummer H3T Manual
Page 233 highlights
Driving Your Vehicle Maintenance When Trailer Towing The vehicle needs service more often when pulling a trailer. See this manual's Maintenance Schedule or Index for more information. Things that are especially important in trailer operation are automatic transmission fluid, engine oil, axle lubricant, belts, cooling system and brake system. It is a good idea to inspect these before and during the trip. Check periodically to see that all hitch nuts and bolts are tight. 4-51 Trailer Wiring Harness Light-Duty Trailer Wiring Package If the vehicle does not have a trailer towing package, the chassis harness will contain the following blunt cut circuits: Heavy-Duty Trailer Wiring Package • Yellow: Left Stop/Turn Signal • Dark Green: Right Stop/Turn Signal • White: Ground • Brown: Tail Lamps To add a trailer towing wiring package, have it installed by your dealer/retailer or a qualified service center. Also, see Add-On Electrical Equipment on page 5-91 for more information. If the vehicle has a trailer towing package, the rear bumper harness will have a seven-pin universal heavy-duty trailer connector attached to a bracket on the hitch platform.