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

Operating Instructions
Starting Procedure — Cold Weather
In addition to the previous “Normal Starting Procedures,” use
these Cold Weather Starting guidelines when the air temperature
falls below a certain temperature. Check your Engine
Operation and Maintenance Manual for further details on
when cold weather starting aids are needed.
Using special cold-starting equipment will help the engine
start easier. And in cold weather, fast engine starting helps
relieve the loads on the electrical system and cranking motor.
If you follow these few simple guidelines, you will extend the
service life of your vehicle's engine:
• Keep the electrical system in top condition.
• Use the best quality and recommended grade of fuel
(see Engine Operation and Maintenance Manual).
• Use the recommended engine lubricating oil.
• As stated in the Normal Starting Procedures, when temperatures
are below normal, fully depress the accelerator
pedal after engaging the starter.
Engine Block Heater (Option)
Operating the Engine
To preheat the engine before starting, plug the optional
engine block heater into a properly grounded AC electrical
source. Do not start the engine with the heater plugged in.
WARNING! Engine block heaters can cause fires
resulting in serious personal injury and/or property
damage if not properly maintained and
operated. Regularly inspect the engine block
heater wiring and connector for damaged or
frayed wires. Do not use the heater if there are
any signs of problems. Contact your Authorized
Service Center or the manufacturer of the heater
if you are in need of repairs or information.
CAUTION: Always unplug the heater before
starting the engine. Damage to the cooling system
could occur if the heater is not turned OFF
(unplugged).
When the temperature falls below 0°F (–18°F) for Caterpillar
engines, or –10°F (–24°C) for Cummins engines, the block
heater is required.
Medium Duty (R10/06) Y53-6008 – 61 –