2012 GMC Sierra Owner's Manual - Page 484

10-98 Vehicle Care 6. Use an adequate clamping device designed for towing to ensure that the front wheels are locked into the straight position. Appearance Care Exterior Care Washing the Vehicle To preserve the vehicle's finish, wash it often and out of direct sunlight. Notice: Do not use petroleum based, acidic, or abrasive cleaning agents as they can damage the vehicle's paint, metal, or plastic parts. If damage occurs, it would not be covered by the vehicle's warranty. Approved cleaning products can be obtained from your dealer. Follow all manufacturer directions regarding correct product usage, necessary safety precautions, and appropriate disposal of any vehicle care product. Notice: Avoid using high pressure washes closer than 30 cm (12 in) to the surface of the vehicle. Use of power washers exceeding 8,274 kPa (1,200 psi) can result in damage or removal of paint and decals. Rinse the vehicle well, before washing and after, to remove all cleaning agents completely. If they are allowed to dry on the surface, they could stain. Dry the finish with a soft, clean chamois or an all-cotton towel to avoid surface scratches and water spotting. { WARNING Shifting a four-wheel-drive vehicle's transfer case into N (Neutral) can cause the vehicle to roll even if the transmission is in P (Park). The driver or others could be injured. Make sure the parking brake is firmly set before the transfer case is shifted to N (Neutral). 7. Shift the transfer case to N (Neutral). See "Shifting into Neutral" under Four-Wheel Drive on page 9‑40 for the proper procedure to select the neutral position for the vehicle. 8. Turn the ignition to LOCK/OFF. After towing, see "Shifting Out of Neutral" under Four-Wheel Drive on page 9‑40. Finish Care Application of aftermarket clearcoat sealant/wax materials is not recommended. If painted surfaces are damaged, see your dealer to have the damage assessed and repaired. Foreign materials such as calcium chloride and other salts, ice melting agents, road oil and tar, tree sap, bird droppings, chemicals from industrial chimneys, etc., can damage the vehicle's finish if they remain on painted surfaces. Wash the vehicle as soon as possible. If necessary, use non-abrasive