GMC 2010 T-Series Owner's Manual page 250

1 Replace fuel filter (or every 750 hours of engine
operation, whichever occurs first).
1 Chassis lubrication service (or every 6 months,
whichever occurs first). (10)
1 Inspect door hinge pins and bushings and replace
as necessary.
1 Check restraint system. (34)
1 Steering system service. (11)
1 Front and rear suspension service. (12)
1 Spring-to-axle U-bolts and shackle bolts
service. (14)
1 Exhaust system service (or every 6 months,
whichever occurs first). (2) (3) (15)
1 Wheel bearing (grease type) service (and
whenever hubs are removed). (19) (30)
1 Wheels and tires service. (13)
1 Adjust valve lash (or every 2,625 hours of engine
operation, whichever occurs first). (16)
1 Hydraulic brake service (or every 6 months,
whichever occurs first). (6) (30)
1 Parking brake service (or every 6 months,
whichever occurs first). (7)
1 Air brake service (or every 6 months, whichever
occurs first). (26)
6-12
1 Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first). (27)
1 Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
1 Clean air brake application valve (or every
3 months, or every 300 hours, whichever occurs
first). Lubricate linkage.
1 Air brake chamber service (or every 2 months,
whichever occurs first). (28)
1 Air compressor dry element pleated paper air
strainer service (or every 2 months, or every
800 hours, whichever occurs first).
1 Thermostatically controlled engine cooling fan
service. (3) (17)
1 Shields and underhood insulation
service. (3) (4) (18)
108 000 km (67,500 Miles)
1 Check fluid levels (or every 3 months, whichever
occurs first). (1) (5)
1 Chassis lubrication service (or every 6 months,
whichever occurs first). (10)