6-46 Air Brake Systems (If Equipped)
If you have air brakes, it is important to get rid of
moisture in the system. Moisture will damage your
system if it isn't removed daily.
There are two ways to do this. One is automatic if your
air
-brake vehicle has the optional moisture ejector.
If your vehicle doesn't have that option, however, you
must drain the air reservoirs occasionally to be sure the
air dryer is working properly.
Drain the air brakes at full system pressure. To be sure
you're at full pressure, check your air pressure gage.
It should read at least 100 psi (692 kPa).
Moisture Ejector (Option)
If you have air brakes with a moisture ejector, the valve
automatically ejects moisture from the reserve tank
when the air compressor cycles.
Air Dryer
If your vehicle has air brakes, you have an air dryer.
This collects and removes dirt, moisture or other foreign
matter from the air prior to entering the brake system.
It is mounted on the passenger's side frame rail.
If your dryer is a Bendix
-Westinghouse, it has a
filter that you need to change at intervals. See your
Maintenance Schedule for more about servicing
this filter.
6-90 Rear Axle Lubricant Capacity
Single Speed Axle Pints (Liters). . . . . . . . . . . . . . . .
80 10.0 (4.7). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
S135 26.0 (12.3). . . . . . . . . . . . . . . . . . . . . . . . . . . .
19060S 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . . . . . .
21060D 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . . . . . .
21060S 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . . . . . .
S150 28.0 (13.0). . . . . . . . . . . . . . . . . . . . . . . . . . . .
23090S 40.0 (19.0). . . . . . . . . . . . . . . . . . . . . . . . . .
23105S 56.0 (26.5). . . . . . . . . . . . . . . . . . . . . . . . . .
26105S 54.0 (25.5). . . . . . . . . . . . . . . . . . . . . . . . . .
Tw o
-Speed Axle Pints (Liters). . . . . . . . . . . . . . . . .
19060T 38.0 (18.0). . . . . . . . . . . . . . . . . . . . . . . . . .
21060T 38.0 (18.0). . . . . . . . . . . . . . . . . . . . . . . . . .
23082T 40.0 (19.0). . . . . . . . . . . . . . . . . . . . . . . . . .
26080T 44.0 (20.8). . . . . . . . . . . . . . . . . . . . . . . . . .
Tandem Axles Pints (Liters). . . . . . . . . . . . . . . . . . .
DS344 (front) 32.0 (15.1). . . . . . . . . . . . . . . . . . . . .
RS344 (rear) 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . .
DSH44 (front) 32.0 (15.1). . . . . . . . . . . . . . . . . . . . .
RSH44 (rear) 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . .
DS404, DS404P (front) 32.0 (15.1). . . . . . . . . . . . . .
RS404 (rear) 31.0 (14.7). . . . . . . . . . . . . . . . . . . . . .
Air Conditioning Refrigerant
Capacity
If you do your own service work, you'll need the proper
service manual. See ªDoing Your Own Service Workº in
the Index for additional information. It is recommended
that service work on your air conditioning system be
performed by a qualified technician.
Air Conditioning Refrigerant
R134a 2.1 lbs. (1.0 kg). . . . . . . . . . . . . . . . . . . . . . .
Use Refrigerant Oil, R143a Systems
Normal Maintenance
Replacement Parts
Allison Transmission External Filters
See the Allison Transmission Operator's Manual in your
vehicle for external filter part numbers and information.
Air Compressor Filter
Air Compressor Part Number
Bendix Tu
-Flo
550 (13.2 CFM)2467368
6-91 Service Replacement Part and Filter Recommendations
Engine 7.2L 8.1L 7.8L 6.6L
RPO LG5 L18 LG4 LB7
Spark Plug
ACDelco
41-983
Gap 0.060 inch (1.52 mm)
Torque 14.75 lb. ft. (20.0 Nm)
Oil Filter
CAT
1R0739 ACDelco PF454GM Part No. 94392475
ACDelco PF1218
Air Cleaner Donaldson P522606
ACDelco
A1518CC4/C5 Models:
GM Part No. 88937527
C6/C7/C8 Models:
GM Part
No. 88937548***C4/C5 Models:
GM Part No. 88937527
C6/C7/C8 Models:
GM Part No. 88937548***
Fuel Filter
ACDelco
915 Primary**ACDelco GF626*GM Part No. 94392474 GM Part No. 97256734
6-92
Engine 7.2L 8.1L 7.8L 6.6L
Power Steering
Fluid FilterGM Part
No. 88892858GM Part
No. 88892858GM Part
No. 88892858GM Part
No. 88892858
Secondary
Fuel FilterCAT
1R0751GM Part
No. 25055052GM Part
No. 15098649
Pressure Caps
RC
-54GM Part
No. 15997145GM Part
No. 15075118GM Part
No. 15075118
*Optional Davco (K28) D350921 spin
-on type filter
located on driver's side frame rail.
**Optional Cold Weather (KUK) Racor B6484GM
spin
-on type filter located on driver's side frame rail.*** Optional air filter (GM Part No. 88937525)
for C6/C7/C8 Models. Fits inside standard size filter
(GM Part No. 88937548) listed previously.
7-5
Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown after 100,000 miles
(166 000 km) should be repeated at the same miles (km)
after those intervals for the life of this vehicle.
Gasoline engine vehicles have a computer that lets you
know when to change your engine oil. This is not based
on mileage, but on engine revolutions and engine
operating temperature. When the computer has
calculated that the oil needs changing, the GM Oil Life
System will indicate that a change is necessary.
The ªFootnotesº at the end of this Maintenance
Schedule further explain maintenance services.
See ªScheduled Maintenance Supplementsº earlier in
this section.
100 Miles (160 km)
Wheel stud nut service. (46)
1,000 Miles (1 600 km)
Wheel stud nut service. (46)
Rear axle air shift motor service.(11)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
7,500 Miles (12 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Wheels and tires service. (15)
Parking brake service (or every 6 months, whichever
occurs first). (8)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
10,000 Miles (16 000 km)
DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever
occurs first). (2)(3)
7-6
15,000 Miles (24 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
DURAMAX Diesel Only: Replace fuel filter.
Steering system service. (13)
Front and rear suspension service. (14)
Spring
-to-axle U-bolts and shackle bolts
service. (16)
Exhaust system service (or every 6 months,
whichever occurs first). (3)(4)(17)
Wheels and tires service. (15)
Hydraulic brake service (or every 6 months,
whichever occurs first). (7)(46)
Parking brake service (or every 6 months, whichever
occurs first). (8)
Thermostatically controlled engine cooling fan
service. (4)(20)
Shields and underhood insulation service. (4)(5)(21)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
20,000 Miles (32 000 km)
DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)
Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
22,500 Miles (36 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Inspect door hinge pins and bushings and replace
as necessary.
Cooling system service. Clean the cooling system
filler cap with clean water, clean the core, pressure
test the cap and the system for proper pressure
capability and inspect condition of cooling and
heater hoses and clamps. Replace hoses if cracked,
swollen or damaged.
7-7
Wheel bearing (grease type) service (or every
24 months, whichever occurs first, and whenever
hubs are removed). (23)(46)
Wheels and tires service. (15)
Parking brake service (or every 6 months, whichever
occurs first). (8)
Air intake system service (or every 24 months,
whichever occurs first). (4)(5)(24)
Evaporative Control System service (if equipped) (or
every 24 months, whichever occurs first). (3)(26)
Rear axle air shift motor service. (11)
Air brake service (or every 6 months, whichever
occurs first). (39)
Air brake automatic slack adjuster service
(or every 500 hours, whichever occurs first). (40)
Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first); lubricate
linkage.
Air brake chamber service (or every 2 months,
whichever occurs first). (41)Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever
occurs first). (42)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
30,000 Miles (48 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
DURAMAX Diesel Only: Replace fuel filter.
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Replace fuel filter(s) (or every 12 months, whichever
occurs first). (3)
Steering system service. (13)
Front and rear suspension service. (14)
Spring
-to-axle U-bolts and shackle bolts
service. (16)
Exhaust system service (or every 6 months,
whichever occurs first). (3)(4)(17)
(Continued)
7-8
30,000 Miles (48 000 km) (Continued)
Wheels and tires service. (15)
Hydraulic brake service (or every 6 months,
whichever occurs first). (7)(46)
Parking brake service (or every 6 months, whichever
occurs first). (8)
C600, C700 and C800 Gasoline Engines Only:
Engine drive belts service (or every 12 months,
whichever occurs first). (18)
Thermostatically controlled engine cooling fan
service. (4)(20)
Shields and underhood insulation service. (4)(5)(21)
L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
37,500 Miles (60 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Wheels and tires service. (15)
Parking brake service (or every 6 months, whichever
occurs first). (8)L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
40,000 Miles (64 000 km)
DURAMAX Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)
Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
45,000 Miles (72 000 km)
Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See ªEngine Oilº in the Index. (3)(9)
Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
DURAMAX Diesel Only: Replace fuel filter.
Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Cooling system service. Clean the cooling system
filler cap with clean water, clean the core, pressure
test the cap and the system for proper pressure
capability and inspect condition of cooling and
heater hoses and clamps. Replace hoses if cracked,
swollen or damaged.