Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil.
The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection.
Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.
See also:
After Off-Road Driving
Remove any brush or debris that has collected on the underbody or chassis, or under the hood. These accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings cleaned ...
Capacities and Specifications
Engine Specifications
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Exterior
While GM is trying to differentiate the Silverado and Sierra, the common
silhouette is hard to overcome, even with unique front fenders, grille, bumpers,
headlamps, cargo box and taillamps. There' ...