2008 GMC Acadia Owner's Manual - Page 359

Headlamp Aiming Headlamp aim has been preset at the factory and should need no further adjustment. However, if your vehicle is damaged in a crash, the headlamp aim may be affected. Aim adjustment to the low-beam headlamps may be necessary if oncoming drivers flash their high-beam headlamps at you (for vertical aim). If the headlamps need to be re-aimed, it is recommended that you take the vehicle to your dealer/retailer for service. Halogen Bulbs {CAUTION: Halogen bulbs have pressurized gas inside and can burst if you drop or scratch the bulb. You or others could be injured. Be sure to read and follow the instructions on the bulb package. Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 5-46. For any bulb changing procedure not listed in this section, contact your dealer/retailer. 5-45