Maintenance when Trailer Towing
The vehicle needs service more often when pulling a trailer. See Maintenance Schedule on page 11‑3. 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.
See also:
Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle.
Do not add any electrical equipment. See Add-On Electrical Equipment on page 9‑64.
Added electrical equipment ...
All Terrain chassis and suspension
Based on the chassis of the 2011 Sierra HD trucks, the All Terrain HD
features a fully boxed steel frame with exceptional strength and torsional
stiffness. It incorporates the production models' n ...
New Vehicle Break-In
Notice: The vehicle does not need an elaborate break-in. But it will perform better in the long run if you follow these guidelines:
• Keep the vehicle speed at 88 km/h (55 mph) or less for the firs ...





