of driving (engine break-in period). You will get a more accurate
measurement after 2,000 miles-3,000 miles (3,000 km–5,000 km).
Filling the tank
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in theRefill capacities
section of this chapter.
The advertised capacity is the amount of the indicated capacity and the
empty reserve combined. Indicated capacity is the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.
The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your
vehicle after the fuel gauge indicates empty, you might not be
able to refuel the full amount of the advertised capacity of the
fuel tank due to the empty reserve still present in the tank.
For consistent results when filling the fuel tank:
•Turn the engine/ignition switch to the off position prior to refueling,
an error in the reading will result if the engine is left running.
•Use the same filling rate setting (low — medium — high) each time
the tank is filled.
•Allow no more than two automatic click-offs when filling.
•Always use fuel with the recommended octane rating.
•Use a known quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in miles or kilometers).
2. Each time you fill the tank, record the amount of fuel added (in
gallons or liters).
3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.
2006 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
242
Fluid Ford Part Name Capacity
Fuel tank N/A 19.0 gallons (71.9L)
Rear axle lubricant
5Motorcraft SAE
80W-90 Premium Rear
Axle Lubricant5.0 pints (2.4L)7
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.
5Rear axles are considered lubricated for life when the vehicle is used for
normal service. See yourscheduled maintenance informationfor
Severe Duty requirements.
6Use of synthetic or synthetic blend motor oil is not mandatory. Engine
oil need only meet the requirements of Ford specification
WSS-M2C930-A and the API Certification mark.
7Service refill capacities are determined by filling the rear axle 1/4 inch
to 9/16 inch (6 mm to 14 mm) below the bottom of the filler hole.
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