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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
Refer to the scheduled maintenance guide for the service interval
schedules. If adding fluid is necessary, use only MERCON AT 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).
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.
M AX
M I
N
M AX
M IN
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(tbr)
Owners Guide (post-2002-fmt)
USA English (fus)
Maintenance and Specifications
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BRAKE FLUID RESERVOIR
The fluid level will drop slowly as
the brakes wear, and will rise when
the brake components are replaced.
Fluid levels between the“MIN ”and
“ MAX ”lines 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
The 5R55S transmission does not have a transmission fluid dipstick.
Refer to your scheduled maintenance guide for 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.
Transmission fluid should be checked and, if required, fluid
should be added by a qualified technician.
Before adding any fluid, make sure the correct type is used. Use only
MERCON V automatic transmission fluid. The type of fluid used is
indicated on the transmission fluid pan, extension housing and also in
the Lubricant specifications section in this chapter.
Use of a non-approved automatic transmission fluid may cause
internal transmission component damage and void the warranty.
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 MAINTENANCE
Refer to the scheduled maintenance guide for the appropriate intervals
for changing the air filter element.
When changing the air filter element, use only the Motorcraft air filter
element listed. Refer to Motorcraft Part Numbers .
Note: Do not start your engine with the air cleaner removed and do not
remove it while the engine is running.
MAX
MIN
2004 Thunderbird (tbr)
Owners Guide (post-2002-fmt)
USA English (fus)
Maintenance and Specifications
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Fluid Ford PartNameApplication Capacity
Engine coolant
2Motorcraft
Premium Gold
Engine Coolant
(yellow-colored) 3.9L-4V V8
engine
11.3L (11.9
quarts)
Power steering
fluid Motorcraft
MERCON
AT F All Fill to MAX line
on reservoir
Rear axle
3Motorcraft SAE
75W-90 Fuel
Efficient High
Performance
Synthetic Rear
Axle Lubricant All 1.2
–1.3L
(2.5 –2.7 pints)
Fuel tank N/A All 68.2L (18.0 gallons)
Transmission
fluid
4Motorcraft
MERCON V
AT F Automatic
(5R55S)
11.2L (11.9
quarts)5
Windshield
washer fluidMotorcraft
Premium
Windshield
Washer
ConcentrateAll Fill to line on
reservoir
1Use only brake fluids certified to meet Ford specifications. Refer to
Lubricant Specifications in this chapter. DOT 3 fluid is recommended.
However, if DOT 3 is not available, DOT 4 fluid can be used.
2Add the coolant type originally equipped in your vehicle.3Your vehicle ’s rear axle is filled with a synthetic rear axle lubricant and
is considered lubricated for life. These lubricants do not need to be
checked or changed unless a leak is suspected, service is required or the
axle assembly has been submerged in water. The axle lubricant should
be changed any time the rear axle has been submerged in water. Fill 6
mm to 14 mm (1/4 inch to 9/16 inch) below bottom of fill hole.
4Ensure the correct automatic transmission fluid is used. MERCON and
MERCON V are not interchangeable. DO NOT MIX MERCON and
MERCON V. Refer to the scheduled maintenance guide to determine
the correct service interval.
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USA English (fus)
Maintenance and Specifications
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Item Ford partnameFord part
number Ford
specification
Lock cylinders Motorcraft Penetrating and
Lock LubricantXL-1 none
Power steering
fluid Motorcraft
MERCON
AT F XT-2-QDX MERCON
Rear Axle
Lubricant Motorcraft SAE
75W-90 Fuel
Efficient High
Performance
Synthetic Rear
Axle Lubricant
2
XY-75W90-QFEHP
Automatic
transmission
fluid Motorcraft
MERCON
V
AT F
3
XT-5-QM MERCON V
Windshield
washer fluid Motorcraft
Premium
Windshield
Washer
ConcentrateZC-32-A WSB-M8B16
–A2
1Use only brake fluids certified to meet Ford specifications. DOT 3 fluid
is recommended. However, if DOT 3 is not available, DOT 4 fluid can be
used.
2Ford design rear axles contain a synthetic lubricant that does not
require changing unless the axle has been submerged in water.
3Ensure the correct automatic transmission fluid is used. MERCON and
MERCON V are not interchangeable. DO NOT MIX MERCON and
MERCON V. Refer to the scheduled maintenance guide to determine
the correct service interval.
2004 Thunderbird (tbr)
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USA English (fus)
Maintenance and Specifications
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