GMC 2006 Sierra 1500 Pickup Owner's Manual page 554

Scheduled Maintenance (cont'd)
Service Maintenance I Maintenance II
Perform any needed additional services. See "Additional Required Services" in
this section.
Inspect suspension and steering components. See footnote (b).
Inspect engine cooling system. See footnote (c).
Inspect wiper blades. See footnote (d).
Inspect restraint system components. See footnote (e).
Lubricate body components. See footnote (f).
Check transmission fluid level and add fluid as needed.
Inspect shields, vehicles with diesel engine or with GVWR above
10,000 lbs (4 536 kg) only. See footnote (n).
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