OPERATOR'S MANUAL

Engine Cooling System Preventive Maintenance
– 182 – Y53-6027
Medium Duty (R05/09)
Engine (Block) Heater (option)
WARNING! Do not use the heater if there are any
signs of problems. Engine block heaters can
cause fires resulting in death, 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. Contact your Autho-
rized Service Center or the manufacturer of the
heater if you are in need of repairs or informa-
tion.
CAUTION: Always unplug the block heater
before starting your engine. Damage to the cool-
ing system could occur if not turned OFF
(unplugged).
Use a solution of half ethylene glycol antifreeze and half
water for best heater performance. Do not use more than 65
percent concentration of antifreeze, as a shortened heater
life will result.
After servicing the cooling system, operate the vehicle for a
day or two before using the heater. Trapped air inside the
engine needs time to escape.
PREVENTIVE MAINTENANCE (PM) INTERVALS
I
AB C D E
At the first 15,000 mi./
24,000 km or at the first
PM
15,000 mi./24,000 km/
Monthly
30,000 mi./48,000 km 60,000 mi./96,000 km/
6 months
120,000 mi./
192,000km / Annually
240,000 mi./384,000 km
SYSTEM COMPONENT MAINTENANCE TASK
Recommended
PM Interval
I ABCDE