Coolant Surge Tank Pressure Cap
The coolant surge tank
pressure cap must be fully
installed on the coolant
surge tank.
Notice:Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See“Capacities and Specifications”for more
information.
Engine Overheating
You willfind a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-36. In addition, you will
find a LOW COOLANT, ENGINE OVERHEATED and a
REDUCED ENGINE POWER message in the DIC on
the instrument panel. SeeDriver Information Center
(DIC) on page 3-42.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternatesfiring
groups of cylinders helps prevent engine damage. In
this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. See“Engine Oil”in the Index.
5-26
2003 - Sierra Denali
Engine Specifications
Engine VIN Code Type Spark Plug Gap
VORTEC™6000 U V8 0.060 inches (1.52 mm)
Wheels and Tires
Wheel Nut Torque 140 lb ft (190Y)
Tire Pressure See the Certification/Tire label on the rear edge of the
driver’s door.
Normal Maintenance
Replacement Parts
Part Number
Oil Filter*PF44
Engine Air Cleaner/Filter* A1518C
Passenger Compartment Air Filter Kit** 52485513
PCV Valve*CV2001–C
Spark Plugs41–974*/PZTR5A15 NGK
Fuel Filter*GF626
Wiper Blades**15153642
TypeITTA
*ACDelco
®Part No.
**GM Part No.
5-100
2003 - Sierra Denali