2021 FORD F-350 service interval

exported to non- ultra low sulfur diesel fuel
markets will need to be retrofitted at the
customer
’s expense using Ford authorized
dealer service parts in order to be reliably
operated on non- ultra low sulfur diesel
fuel.
Biodiesel WARNING: Do not mix diesel with
gasoline, gasohol or alcohol. This could
cause an explosion.
Note: Do not use home heating oil,
agricultural fuel, raw fats and oils, waste
cooking greases, biodiesel greater than 20%
or any diesel not intended for highway use.
Damage to the fuel injection system, engine
and exhaust catalyst, and diesel particulate
filter can occur if you use an improper fuel.
Red dye is used to identify fuels intended
for agricultural and non-highway use.
You may operate your vehicle on diesel
fuels containing up to 20% biodiesel, also
known as B20.
Biodiesel fuel is a chemically converted
product from renewable fuel sources, such
as vegetable oils, animal fats and waste
cooking greases.
To help achieve acceptable engine
performance and durability when using
biodiesel in your vehicle:
• Confirm the biodiesel content of the
fuel to be B20 (20% biodiesel) or less
• Only use biodiesel fuel of good quality
that complies with industry standards
• Follow the recommended service
maintenance intervals
See General
Maintenance Information (page 565). •
Do not store biodiesel fuel in the fuel
tank for more than 1 month
• Consider changing brands or reducing
biodiesel content if you have cold
temperature fuel gelling issues or a
frequent LOW FUEL PRESSURE
message appearing
Use of biodiesel in concentrations greater
than 20% may cause damage to your
vehicle, including engine and/or exhaust
after-treatment hardware (exhaust
catalyst and particulate filter) failures.
Concentrations greater than 20% can also
cause fuel filter restrictions that may result
in a lack of power or damage to fuel
system components, including fuel pump
and fuel injector failures.
We recommend SAE 5W-40 oil for fuels
with greater than 5% biodiesel (B5). For
more information about oil change
intervals and other maintenance when
operating on biodiesel
See Special
Operating Conditions Scheduled
Maintenance
(page 574).
Look for a label on the fuel pump to
confirm the amount of biodiesel contained
in a diesel fuel. Biodiesel content is often
indicated with the letter B followed by the
percent of biodiesel in the fuel. For
example, B20 indicates a fuel containing
20% biodiesel. Ask the service station
attendant to confirm the biodiesel content
of a diesel fuel if you do not see a label on
the fuel pump.
Biodiesel fuels degrade more easily than
diesel fuels not containing biodiesel and
should not be stored in the fuel tank for
more than 1 month. If you plan to park or
store your vehicle for more than 1 month,
then you should empty your vehicle fuel
tank of biodiesel fuel. You should fill the
tank with a pure petroleum-based diesel
fuel and run your vehicle for a minimum of
30 minutes.
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•
The tire air pressures recommended
for general driving are on the vehicle ’s
Safety Certification Label. The
maximum cold inflation pressure for
the tire and associated load rating is
on the tire sidewall. Tire air pressure
may require re-adjustment within these
pressure limits to accommodate the
additional weight of the snowplow
installation.
• Federal and some local regulations
require additional exterior lamps for
snowplow-equipped vehicles. Consult
your authorized dealer for additional
information.
Operating the Vehicle with the
Snowplow Attached
Note: Do not use your vehicle for snow
removal until you have driven at least
500 mi (800 km).
Ford recommends vehicle speed does not
exceed
45 mph (72 km/h) when
snowplowing.
If transporting a snowplow in summertime,
cooling system airflow may be blocked by
the snowplow. Change the snowplow
height or position to improve airflow to the
radiator or limit your vehicle speed to a
maximum of
45 mph (72 km/h).
The attached snowplow blade restricts
airflow to the radiator, and may cause the
engine to run at a higher temperature:
Attention to engine temperature is
especially important when outside
temperatures are above freezing. Angle
the blade to maximize airflow to the
radiator and monitor engine temperature
to determine whether a left or right angle
provides the best performance.
Follow the severe duty schedule in your
Scheduled Maintenance information for
engine oil and transmission fluid change
intervals. Snowplowing with your Airbag
Equipped Vehicle WARNING:
Do not attempt to
service, repair, or modify the
supplementary restraint system or
associated components. Failure to
follow this instruction could result in
personal injury or death. WARNING:
All occupants of your
vehicle, including the driver, should
always properly wear their seatbelts,
even when an airbag supplemental
restraint system is provided. Failure to
properly wear your seatbelt could
seriously increase the risk of injury or
death. WARNING:
Modifying or adding
equipment to the front end of your
vehicle (including hood, bumper system,
frame, front end body structure, tow
hooks and hood pins) may affect the
performance of the airbag system,
increasing the risk of injury. Do not
modify or add equipment to the front
end of your vehicle.
Note: Please refer to the Body Builders
Layout Book for instructions about the
appropriate installation of additional
equipment.
Your vehicle is equipped with a driver and
passenger airbag supplemental restraint
system. The supplemental restraint system
will activate in certain frontal and offset
frontal collisions when the vehicle sustains
sufficient frontal deceleration.
Careless or high speed driving while
plowing snow that results in sufficient
vehicle decelerations can deploy the
airbags. Such driving also increases the risk
of accidents.
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Engine lubrication for severe
service operation
The following conditions define severe
operation for which engine operation with
SAE 5W-40 oil which meets Ford
specification, WSS-M2C171-F1, is
recommended. Oil and oil filter change
intervals will be determined by the
Intelligent Oil Life Monitor™ as noted
previously.
ENGINE OIL CHECK - 7.3L
To check the engine oil level consistently
and accurately, do the following:
1.
Make sure the parking brake is on. Make
sure the transmission is in park (P) or
neutral (N).
2. Run the engine until it reaches normal operating temperature.
3. Make sure that your vehicle is on level ground.
4. Switch the engine off and wait 15 minutes for the oil to drain into the oil
pan. Checking the engine oil level too
soon after you switch the engine off
may result in an inaccurate reading.
5. Open the hood. See Scheduled
Maintenance (page 565).
6. Remove the dipstick and wipe it with a clean, lint-free cloth. See
Scheduled Maintenance (page 565).
7. Replace the dipstick and remove it again to check the oil level. See
Scheduled Maintenance (page 565).
8. Make sure that the oil level is between
the maximum and minimum marks. If
the oil level is at the minimum mark,
add oil immediately. See
Capacities
and Specifications (page 441).
9. If the oil level is correct, replace the dipstick and make sure it is fully seated. Note:
Do not remove the dipstick when the
engine is running.
Note: If the oil level is between the
maximum and minimum marks, the oil level
is acceptable. Do not add oil.
Note: The oil consumption of new engines
reaches its normal level after approximately
3,000 mi (5,000 km)
.
Adding Engine Oil WARNING: Do not remove the filler
cap when the engine is running.
Do not use supplemental engine oil
additives because they are unnecessary
and could lead to engine damage that may
not be covered by the vehicle Warranty. Only use oils certified for gasoline engines
by the American Petroleum Institute (API).
An oil with this trademark symbol
conforms to the current engine and
emission system protection standards and
fuel economy requirements of the
International Lubricants Specification
Advisory Committee (ILSAC).
To top up the engine oil level do the
following:
1. Clean the area surrounding the engine
oil filler cap before you remove it.
2. Remove the engine oil filler cap.
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3. Add engine oil that meets the correct
specification.
4. Recheck the oil level.
5. If the oil level is correct, replace the dipstick and make sure it is fully seated.
6. Replace the engine oil filler cap. Turn it clockwise until you feel a strong
resistance.
Note: Do not add oil further than the
maximum mark. Oil levels above the
maximum mark may cause engine damage.
Note: Make sure you install the oil filler cap
correctly.
Note: Soak up any spillage with an
absorbent cloth immediately.
CHANGING THE ENGINE OIL
AND OIL FILTER
If your vehicle is equipped with a diesel
engine, an Intelligent Oil Life Monitor™
calculates the proper oil change service
interval. When the information display
indicates: OIL CHANGE REQUIRED, change
the engine oil and oil filter. See
Information Displays (page 110).
The engine oil filter protects your engine
by filtering harmful, abrasive or sludge
particles and particles significantly smaller
than most available will-fit filters. See
Motorcraft Parts
(page 443).
1. Unscrew the oil filter and oil pan drain plug and wait for the oil to drain.
2. Replace the filter.
Note: Do not handle hot oil filter with bare
hands.
3. Reinstall the oil pan drain plug.
4. Refill the engine with new oil. See Engine Oil Capacity and
Specification
(page 449). 5. For diesel engines, you need to reset
the Intelligent Oil Life Monitor™. See
Information Displays
(page 110).
Engine lubrication for severe
service operation
The following conditions define severe
operation for which engine operation with
SAE 5W-40 that meets our specification
WSS-M2C171-F1 is recommended. Oil and
oil filter change intervals will be
determined by the Intelligent Oil Life
Monitor™ as noted previously.
• Frequent or extended idling (over 10
minutes per hour of normal driving).
• Low-speed operation/stationary use.
• If vehicle is operated in sustained
ambient temperatures below
-9°F
(-23°C) or above 100°F (38°C).
• Frequent low-speed operation,
consistent heavy traffic less than
25 mph (40 km/h)
.
• Operating in severe dust conditions.
• Operating the vehicle off road.
• Towing a trailer over
1,000 mi
(1,600 km).
• Sustained, high-speed driving at Gross
Vehicle Weight Rating (maximum
loaded weight for vehicle operation).
• Use of fuels with sulfur content other
than ultra-low sulfur diesel (ULSD).
• Use of high-sulfur diesel fuel.
OIL CHANGE INDICATOR
RESET
Use the information display controls on
the steering wheel to reset the oil change
indicator.
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From the main menu scroll to:
Action and description
Message
Press the down arrow
button, then from this menu
scroll to the following
message.
Truck Info
Press the OK button.
Mainten-
ance
Monitor
Press the down arrow
button, then from this menu
scroll to the following
message.
Oil Life:
xxx%
Press the
OK button.
Oil Life
Press and hold the
OK
button until the instrument
cluster displays the
following message.
Oil Life
Hold OK to
Reset
Oil Life: 100%
When the oil change indic-
ator resets the instrument
cluster displays 100%.
Repeat the process if the oil
change indicator does not
reset.
CHANGING THE ENGINE AIR
FILTER - 6.2L WARNING:
To reduce the risk of
vehicle damage and personal burn
injuries, do not start your engine with the
air cleaner removed and do not remove
it while the engine is running.
Use the correct specification air filter
element. See
Motorcraft Parts (page
443). Note:
Failure to use the correct air filter
element may result in severe engine
damage. Resulting component damage
may not be covered by the vehicle Warranty.
Change the air filter element at the correct
service interval. See
Scheduled
Maintenance (page 565). 1. Disconnect the mass air flow sensor
electrical connector, if required.
2. Remove the air intake tube securing clamp.
3. Pull the air intake tube away from the air filter housing.
4. Remove the clips that secure the air filter housing cover. Remove the air
filter housing cover.
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x4
1
2
4
3

5.
Remove the air filter element from the
air filter housing.
6. Install in the reverse order.
CHANGING THE ENGINE AIR
FILTER - 6.7L DIESEL WARNING: To reduce the risk of
vehicle damage and personal burn
injuries, do not start your engine with the
air cleaner removed and do not remove
it while the engine is running.
Use the correct specification air filter
element. See
Motorcraft Parts (page
443).
Note: Failure to use the correct air filter
element may result in severe engine
damage. Resulting component damage
may not be covered by the vehicle Warranty.
Change the air filter element at the correct
service interval. See
Scheduled
Maintenance (page 565). 1. Disconnect the mass air flow sensor
electrical connector, if required.
2. Remove the clips (x3) that secure the air filter housing cover. Remove the air
filter housing cover. Disconnect and
pull the air intake tube away, as
needed. 3.
Remove the air filter element from the
air filter housing.
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5 E310318 E310319

At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display.
You may notice a reduction in vehicle
speed caused by reduced engine power in
order to manage the engine coolant
temperature. Your vehicle may enter this
mode if certain high-temperature and
high-load conditions take place. The
amount of speed reduction depends on
vehicle loading, grade and ambient
temperature. If this occurs, there is no
need to pull off the road. You can continue
to drive your vehicle.
The air conditioning may turn on and off
during severe operating conditions to
protect the engine from overheating. When
the coolant temperature decreases to the
normal operating temperature, the air
conditioning turns on.
If the coolant temperature gauge moves
fully into the red zone, or if the coolant
temperature warning or service engine
soon messages appear in your information
display, do the following:
1. Pull off the road as soon as safely
possible and shift the transmission into
park (P).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. After
several minutes, if the temperature
does not drop, follow the remaining
steps.
3. Switch the engine off and wait for it to
cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue. AUTOMATIC TRANSMISSION
FLUID CHECK
Note:
Transmission fluid should be checked
by an authorized dealer. If required, fluid
should be added by an authorized dealer.
The automatic transmission does not have
a transmission fluid dipstick.
Have an authorized dealer check and
change the transmission fluid and filter at
the correct service interval. See your
scheduled maintenance information. 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.
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.
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1. Park your vehicle on a level surface.
2. Look at the brake fluid reservoir to see
where the brake fluid level is relative
to the MIN and the MAX marks on the
reservoir.
Note: If the brake fluid level is between the
MIN
and the MAX marks on the reservoir, it
is acceptable.
Note: If the brake fluid level is below the
MIN
mark or above the MAX mark, have
your vehicle checked as soon as possible.
Note: To avoid fluid contamination, the
reservoir cap must remain in place and fully
tight, unless you are adding fluid.
Only use fluid that meets our
specifications. See
Capacities and
Specifications (page 441).
Brake Fluid Service Interval
Brake fluid absorbs water over time which
degrades the effectiveness of the brake
fluid. Change the brake fluid at the
specified intervals to prevent degraded
braking performance. For detailed interval information, see
Scheduled Maintenance in your Owner's
Manual or your local maintenance guide.
POWER STEERING FLUID
CHECK
Check the power steering fluid. See
Scheduled Maintenance
(page 565). If
adding fluid is necessary, use only
MERCON LV ATF
Check the fluid level when it is at ambient
temperature.
1. Check the fluid level in the reservoir. It should be between the MIN and MAX
range. Do not add fluid if the level is
within this range.
2. If the fluid level is low, add fluid to bring
the fluid level up to between the MIN
and MAX range.
3. Switch the engine on.
4. While the engine idles, turn the steering
wheel left and right several times.
5. Switch the engine off.
6. Recheck the fluid level in the reservoir. Do not add fluid if the level is between
the MIN and MAX range.
7. If the fluid is low, add fluid in small amounts, continuously checking the
level until it is between the MIN and
MAX range. For proper fluid type, See
Capacities and Specifications (page
441). Be sure to put the cap back on the
reservoir.
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