Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
•Idling for long periods of time (greater than one minute) may waste
fuel.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
•Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Revving the engine before turning it off may reduce fuel economy.
•Using the air conditioner or defroster may reduce fuel economy.
•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between third and fourth gear occurs.
Unnecessary shifting of this type could result in reduced fuel
economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toLubricant specificationsin
this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found inscheduled maintenance information.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
232
emission control, such non-Ford parts should be equivalent to genuine
Ford Motor Company parts in performance and durability.
Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine
compartment and exhaust system, which can start a fire.
Illumination of the “Check Engine” light, charging system warning light
or the temperature warning light, fluid leaks, strange odors, smoke or
loss of engine power, could indicate that the emission control system is
not working properly.
Exhaust leaks may result in entry of harmful and potentially
lethal fumes into the passenger compartment.
Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, services,
sells, leases, trades vehicles, or supervises a fleet of vehicles are not
permitted to intentionally remove an emission control device or prevent
it from working. Information about your vehicle’s emission system is on
the Vehicle Emission Control Information Decal located on or near the
engine. This decal identifies engine displacement and gives some tune up
specifications.
Please consult yourWarranty Guidefor complete emission warranty
information.
On board diagnostics (OBD-II)
Your vehicle is equipped with a computer that monitors the engine’s
emission control system. This system is commonly known as the On
Board Diagnostics System (OBD-II). This OBD-II system protects the
environment by ensuring that your vehicle continues to meet
government emission standards. The OBD-II system also assists the
service technician in properly servicing your vehicle. When theCheck
engine/Service engine soonlight illuminates, the OBD-II system has
detected a malfunction. Temporary malfunctions may cause yourCheck
engine/Service engine soonlight to illuminate. Examples are:
1. The vehicle has run out of fuel. (The engine may misfire or run
poorly.)
2. Poor fuel quality or water in the fuel.
3. The fuel cap may not have been securely tightened. SeeFuel filler
capin this chapter.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
234
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel and/or properly tightening the fuel cap. After three
driving cycles without these or any other temporary malfunctions
present, theCheck engine/Service engine soonlight should turn off. (A
driving cycle consists of a cold engine startup followed by mixed
city/highway driving.) No additional vehicle service is required.
If theCheck engine/Service engine soonlight remains on, have your
vehicle serviced at the first available opportunity.
Readiness for Inspection/Maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostics system. If yourCheck engine/Service engine
soonlight is on, refer to the description in theWarning lights and
chimessection of theInstrument Clusterchapter. Your vehicle may not
pass the I/M test with theCheck engine/Service engine soonlight on.
If the vehicle’s powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a “not ready for I/M test”
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
•First, at least 10 minutes of driving on an expressway or highway.
•Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
POWER STEERING FLUID
Check the power steering fluid.
Refer to thescheduled
maintenance informationfor the
service interval schedules.If adding
fluid is necessary, use only
MERCONAT F.
1. Start the engine and let it run until it reaches normal operating
temperature (the engine coolant temperature gauge indicator will be
near the center of the normal area between H and C).
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
235
2. While the engine idles, turn the steering wheel left and right several
times.
3. Turn the engine off.
4. Check the fluid level in the
reservoir. It should be between the
MIN and MAX lines. Do not add
fluid if the level is in this range.
5. If the fluid is low, add fluid in small amounts, continuously checking
the level until it reaches the range between the MIN and MAX lines. Be
sure to put the cap back on the reservoir.
BRAKE FLUID
The fluid level will drop slowly as
the brakes wear, and will rise when
the brake components are replaced.
Fluid levels below the “MAX” line
that do not trigger the brake system
warning lamp are within the normal
operating range, there is no need to
add fluid. If the fluid levels are outside of the normal operating range,
the performance of your brake system could be compromised, seek
service from your dealer immediately.
TRANSMISSION FLUID
Checking automatic transmission fluid (if equipped)
Refer to yourscheduled maintenance informationfor scheduled
intervals for fluid checks and changes. Your transmission does not
consume fluid. However, the fluid level should be checked if the
transmission is not working properly, i.e., if the transmission slips or
shifts slowly or if you notice some sign of fluid leakage.
Automatic transmission fluid expands when warmed. To obtain an
accurate fluid check, drive the vehicle until it is at normal operating
temperature (approximately 20 miles [30 km]). If your vehicle has been
operated for an extended period at high speeds, in city traffic during hot
DONOTOVERFILLPOWERSTEERINGFLUID
MAX
MIN
MAX
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
236
weather or pulling a trailer, the vehicle should be turned off for about 30
minutes to allow fluid to cool before checking.
1. Drive the vehicle 20 miles (30 km) or until it reaches normal operating
temperature.
2. Park the vehicle on a level surface and engage the parking brake.
3. With the parking brake engaged and your foot on the brake pedal,
start the engine and move the gearshift lever through all of the gear
ranges. Allow sufficient time for each gear to engage.
4. Latch the gearshift lever in P (Park) and leave the engine running.
5. Remove the dipstick, wiping it clean with a clean, dry lint free rag. If
necessary, refer toIdentifying components in the engine compartment
in this chapter for the location of the dipstick.
6. Install the dipstick making sure it is fully seated in the filler tube.
7. Remove the dipstick and inspect the fluid level. The fluid should be in
the designated area for normal operating temperature or ambient
temperature.
Low fluid level
Do not drive the vehicle if the fluid
level is at the bottom of the dipstick
and the ambient temperature is
above 50°F (10°C).
Correct fluid level
The transmission fluid should be checked at normal operating
temperature 150°F-170°F (66°C-77°C) on a level surface. The normal
operating temperature can be reached after approximately 20 miles
(30 km) of driving.
You can check the fluid without driving if the ambient temperature is
above 50°F (10°C). However, if fluid is added at this time, an overfill
condition could result when the vehicle reaches normal operating
temperature.
D
O
N
’T
A
D
D
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
237
If an overfill occurs, excess fluid
should be removed by a qualified
technician.
An overfill condition of
transmission fluid may cause
shift and/or engagement
concerns and/or possible
damage.
Do not use supplemental transmission fluid additives, treatments or
cleaning agents. The use of these materials may affect transmission
operation and result in damage to internal transmission components.
AIR FILTER
Refer toscheduled maintenance informationfor the appropriate
intervals for changing the air filter element.
When changing the air filter element, use only the Motorcraft air filter
element listed. Refer toMotorcraft part numbersin this chapter.
Note:Do not start your engine with the air cleaner removed and do not
remove it while the engine is running.
Changing the air filter element
1. Release the clamps that secure the air filter housing cover.
2. Carefully separate the two halves of the air filter housing.
3. Remove the air filter element from the air filter housing.
4. Wipe the air filter housing and cover clean to remove any dirt or
debris and to ensure good sealing.
5. Install a new air filter element. Be
careful not to crimp the filter
element edges between the air filter
housing and cover. This could cause
filter damage and allow unfiltered
air to enter the engine if not
properly seated.
6. Replace the air filter housing cover and secure the clamps.
7. Replace the air inlet tube and secure the clamp.
D
O
N
’T
A
D
D
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
239
Note:Failure to use the correct air filter element may result in severe
engine damage. The customer warranty may be voided for any damage to
the engine if the correct air filter element is not used.
MOTORCRAFT PART NUMBERS
Component 4.6L SOHC V8 engine
Air filter element FA-1668
Fuel filter FG-986B
Battery-standard BXT-65–650
Battery-heavy duty BXT-65–750
Oil filter FL-820-S
PCV valve
1
Spark plugs2
1
The PCV valve is a critical emission component. It is one of the items
listed inscheduled maintenance informationand is essential to the
life and performance of your vehicle and to its emissions system.
For PCV valve replacement, see your dealer or a qualified service
technician. Refer toscheduled maintenance informationfor the
appropriate intervals for changing the PCV valve.
Replace the PCV valve with one that meets Ford material and
design specifications for your vehicle, such as a Motorcraft or
equivalent replacement part. The customer warranty may be void
for any damage to the emissions system if such a PCV valve is not
used.
2For spark plug replacement, see your dealer or a qualified service
technician. Refer toscheduled maintenance informationfor the
appropriate intervals for changing the spark plugs.
Replace the spark plugs with ones that meet Ford material and
design specifications for your vehicle, such as Motorcraft or
equivalent replacement parts. The customer warranty may be
void for any damage to the engine if such spark plugs are not
used.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
240
REFILL CAPACITIES
Fluid Ford Part Name Capacity
Engine oil (includes
filter change)
6Motorcraft SAE 5W-20
Premium Synthetic
Blend Motor Oil (US)
Motorcraft SAE 5W-20
Super Premium Motor
Oil (Canada)6.0 quarts (5.7L)
Brake fluid Motorcraft High
Performance DOT 3
Motor Vehicle Brake
Fluid
1
Fill to line on reservoir
Power steering fluid Motorcraft MERCON
AT FFill to line on reservoir
Transmission fluid
(4R70/75 E)
2Motorcraft
MERCONVATF13.9 quarts (13.2L)3
Engine coolant4Motorcraft Premium
Gold Engine Coolant
(yellow-colored)18.6 quarts (17.6L)
Fuel tank N/A 19.0 gallons (71.9L)
Rear axle lubricant
5Motorcraft SAE
80W-90 Premium Rear
Axle Lubricant5.0 pints (2.4L)
Windshield washer
fluidMotorcraft Premium
Windshield Washer
ConcentrateFill to line on reservoir
1Use only brake fluids certified to meet Ford specifications. Refer to
Lubricant Specificationsin this chapter. DOT 3 fluid is recommended.
However, if DOT 3 is not available, DOT 4 fluid can be used.
2Ensure the correct automatic transmission fluid is used. MERCONand
MERCONV are not interchangeable. DO NOT MIX MERCONand
MERCONV. Refer to thescheduled maintenance informationto
determine the correct service interval.
3Indicates only approximate dry-fill capacity. Some applications may vary
based on cooler size and if equipped with an in-tank cooler. The amount
of transmission fluid and fluid level should be set by the indication on
the dipstick’s normal operating range.
4Add the coolant type originally equipped in your vehicle.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
241