Peterbilt Medium Duty Trucks Operator's Manual after 1-07

Engine Cooling System
NOTE: If frequent topping off is necessary and
there are no visible signs of coolant leaks when
the engine is cold, check for leaks with the engine
operating at normal temperature.
WARNING! Handle coolant and antifreeze carefully.
Ethylene glycol antifreeze is poisonous.
Store in original fluid container only and always
keep out of reach of children.
FILL
COOLANT
EXPANSION
TANK
Preventive Maintenance
Proper Coolant Level
NOTE: Do not overfill a cooling system. Excess
coolant may result in overflow, loss of antifreeze,
and reduced corrosion protection.
Check the coolant level after each trip. Add coolant as
necessary. You may find your coolant level is not up to the
correct level soon after you have filled the radiator. This
may be because all the trapped air in the system has not
yet been purged. It takes a little time for all the air to leave
the system after you fill your radiator.
Refilling Your Radiator
Cooling System Expansion Tank
1. Be sure the radiator and engine block drains are closed.
2. Move the heater control to maximum heat position.
3. Remove the surge tank pressure cap
4. Through the surge tank, fill the system with premixed
coolant. Pour it in a steady flow until the radiator is full.
5. Start the engine.
6. Idle at low RPM.
7. Complete the filling. Do it as quickly as possible.
– 146 – Y53-6008 Medium Duty (R10/06)