GMC Sierra 3500HD 2001 Owner's Manual page 287

Long Trip/Highway Scheduled Maintenance
50,000 Miles (83 000 km)
j
Change automatic transmission fluid and filter. Manual transmission fluid
doesn't require change.
52,500 Miles (87 500 km)
j
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
j
Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
j
Check rear axle fluid level and add fluid as needed.
j
Rotate tires. See "Tire Inspection and Rotation" in the Index for proper
rotation pattern and additional information. (See footnote +.)
DATE
ACTUAL
SERVICED BY:
MILEAGE
DATE
ACTUAL
SERVICED BY:
MILEAGE
7-37