Peterbilt Medium Duty Truck Owner's Manual - Peterbilt Motors

Preventive Maintenance
Air System
Table 5
Air System Scheduled Maintenance
MAXIMUM INTERVALS
TEST
EACH WEEK
EACH MONTH
(10,000 mi) (16,000
km)
THREE MONTHS
(25,000 mi) (40,000
km)
SIX MONTHS
(50,000 mi) (80,000
km)
ANNUALLY
(100,000 mi)
(160,000 km)
Automatic Drain Valve
Safety Valve
Quick Release Valve
Manual Drain Valve
•
•
•
•
Air System Function Test
Scheduled maintenance should be performed on the Medium
Duty vehicle’s air system, as outlined in the Medium Duty
Maintenance Manual and Table 5. In addition, perform an
Air System Function Test at least every 3 months or if there is
any indication of a potential problem.
Air Tanks
The front (secondary) service tank is underneath the cab, on
the driver's side; the wet (supply) tank is underneath the front
service tank, behind the battery box; and the rear (primary)
service tank is attached to the left frame, just behind the cab.
The supply tank (or “wet” tank), must be drained on a daily
basis. Drain the supply tank by pulling the drain valve lanyard.
Hold it open until the escaping air is free of water.
The two service tanks (or “dry” tanks), must be drained on a
weekly basis. Drain the two service tanks by opening the
drain valves. Turn valve handles counter-clockwise, and
leave open until the escaping air is free of water.
WARNING! If the supply and service tanks are
not drained at the recommended frequency,
water could enter the air lines and valves. This
could cause corrosion or blockage, which could
compromise the brake system safety and potentially
cause an accident involving death or injury.
Medium Duty (R05/09) Y53-6027 – 197 –