GMC T-Series 2007 Owner's Manual page 298

❑ Air brake system valve service (or every
3 months, or every 900 hours, whichever
occurs first). (31)
❑ Air intake system service (or every 24 months,
whichever occurs first). (3) (4) (20)
❑ Rear axle air shift motor service. (9)
24,000 Miles (40 000 km)
❑ Lubricate U-joints (or every 6 months,
whichever occurs first).
30,000 Miles (48 000 km)
❑ Vehicles Without Engine Oil Life System Only:
Change engine oil and filter (or every 12 months,
or every 750 hours of engine operation,
whichever occurs first). (2)
❑ Vehicles With Engine Oil Life System Only:
Check oil life system (or every 12 months, or
every 750 hours of engine operation, whichever
occurs first). If engine oil and filter are changed,
reset system. See Engine Oil Life System on
page 209. (2) (8)
298
❑ Inspect engine air cleaner filter change indicator.
If necessary, replace the filter. If vehicle is driven
in dusty/dirty conditions, inspect filter change
indicator at every engine oil change. See Engine
Air Cleaner/Filter on page 211 for more
information.
❑ Check fluid levels (or every 3 months, whichever
occurs first). (1) (5)
❑ Replace fuel filter (or every 750 hours of engine
operation, whichever occurs first).
❑ Chassis lubrication service (or every 6 months,
whichever occurs first). (10)
❑ Steering system service. (11)
❑ Front and rear suspension service. (12)
❑ Spring-to-axle U-bolts and shackle bolts
service. (14)
❑ Exhaust system service (or every 6 months,
whichever occurs first). (2) (3) (15)
❑ Wheel bearing (grease type) service (and
whenever hubs are removed). (19) (30)
❑ Wheels and tires service. (13)
❑ Hydraulic brake service (or every 6 months,
whichever occurs first). (6) (30)