Peterbilt Model 320 Operator's Manual after 8-07 - Peterbilt Motors ...

Engine Cooling System
ELC Extender
Add ELC extender if necessary at the maintenance interval
under "PART 8: MAINTENANCE AND SERVICE".
Coolant Filter
If your vehicle came with a non-chemical filter (“blank filter”),
replace it only with a blank filter at the interval specified
in "PART 8: MAINTENANCE AND SERVICE". Never
use filters that contain SCAs in an ELC filled system.
Topping Off
WARNING! Removing the fill cap on a hot engine
can cause scalding coolant to spray out
and burn you badly. If the engine has been in
operation within the previous 30 minutes, be
very careful in removing the fill cap. Protect
face, hands, and arms against escaping fluid
PART 8: MAINTENANCE AND SERVICE
and steam by covering the cap with a large,
thick rag. Do not try to remove it until the surge
tank cools down if you see any steam or coolant
escaping. In any situation, remove the cap very
slowly and carefully. Be ready to back off if any
steam or coolant begins to escape.
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.
Top off a cooling system when coolant is no longer visible
in the sight glass of a surge tank (if equipped) on a cold
engine. With the engine cold, top up with premixed coolant
of the desired freeze protection concentration. Add coolant
through the pressure cap neck of the surge tank or recovery
bottle. The surge tank or recovery bottle is on top of the
radiator, on the firewall, on the service module, or on the
front of the cab (see next illustration).
– 168 – Y53-6015 R(08/07)