Ford Super Duty (2018 year). Manual — part 85

ENGINE COOLANT CHECK -
6.7L DIESEL

WARNINGS

Never remove the coolant reservoir
cap when the engine is running or
hot.

Do not put coolant in the windshield
washer reservoir. If sprayed on the
windshield, coolant could make it

difficult to see through the windshield.

To reduce the risk of personal injury,
make sure the engine is cool before
unscrewing the coolant pressure

relief cap. The cooling system is under
pressure. Steam and hot liquid can come
out forcefully when you loosen the cap
slightly.

Do not add coolant further than the
MAX mark.

When the engine is cold, check the
concentration and level of the coolant at
the intervals listed in the scheduled
maintenance information. See Scheduled
Maintenance (page 581).

Note: Make sure that the coolant level is
between the MIN and MAX marks on the
coolant reservoir.

Note: Coolant expands when it is hot. The
level may extend beyond the MAX mark.

Maintain coolant concentration within
48% to 50%, which equates to a freeze
point between -30°F (-34°C) and -34°F
(-37°C). Coolant concentration should be
checked using a refractometer. We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentration.

Adding Coolant

WARNINGS

Do not add engine coolant when the
engine is hot. Failure to follow this
instruction could result in personal

injury.

Never remove the coolant reservoir
cap when the engine is running or
hot.

Note: Automotive fluids are not
interchangeable. Do not use coolant or
windshield washer fluid outside of its
specified function and vehicle location.

Note: Do not use stop leak pellets, cooling
system sealants, or non-specified additives
as they can cause damage to the engine
cooling or heating systems. Resulting
component damage may not be covered by
the vehicle Warranty.

It is very important to use prediluted
coolant approved to the correct
specification in order to avoid plugging the
small passageways in the engine cooling
system. See Capacities and
Specifications (page 433). Do not mix
different colors or types of coolant in your
vehicle. Mixing of engine coolants or using
an incorrect coolant may harm the engine
or cooling system components and may
not be covered by the vehicle Warranty.

Note: Coolants marketed for all makes and
models may not be approved to Ford
specifications and may cause damage to
the cooling system. Resulting component
damage may not be covered by the vehicle
Warranty.

If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.

For vehicles with overflow coolant systems
with a non-pressurized cap on the coolant
recovery system, add coolant to the
coolant recovery reservoir when the engine
is cool. Add prediluted coolant to the
maximum level. For all vehicles which have
a coolant degas system with a pressurized
cap, or if it is necessary to remove the
coolant pressure relief cap on the radiator,
follow these steps to add engine coolant:

1.

Turn the engine off and let it cool.

2. Unscrew the cap slowly. Any pressure

escapes as you unscrew the cap.

3. Fill the coolant reservoir slowly with

prediluted engine coolant to within the
minimum and maximum range on the
engine coolant reservoir. If you
removed the radiator cap in an
overflow system, fill the radiator until
the coolant is visible and the radiator
is almost full. If coolant is added to
bring the level within the minimum and
maximum range when the engine is not
cold, the system may remain under
filled.

4. Replace the coolant reservoir cap, turn

it clockwise until you feel a strong
resistance.

5. Check the coolant level in the coolant

reservoir the next few times you drive
your vehicle. If necessary, add enough
prediluted engine coolant to bring the
coolant level to the proper level.

Note: If prediluted coolant is not available,
use the approved antifreeze concentrate
diluting it to 50/50 with distilled water. See
Capacities and Specifications (page 433).
Using water that has not been deionized
may contribute to deposit formation,
corrosion or plugging of the small cooling
system passageways.

If you have to add more than 1.1 qt (1 L) of
engine coolant per month, have your
vehicle checked as soon as possible.
Operating an engine with a low level of
coolant can result in engine overheating
and possible engine damage.

Note: During normal vehicle operation, the
coolant may change color from orange to
pink or light red. As long as the coolant is
clear and uncontaminated, this color change
does not indicate the coolant has degraded
nor does it require the coolant to be drained,
the system to be flushed, or the coolant to
be replaced.

Note: In case of emergency, you can add a
large amount of water without coolant in
order to reach a vehicle service location.
Water alone, without coolant, can cause
engine damage from corrosion, overheating
or freezing. When you reach a service
location, you must have the cooling system
drained, flushed and refilled using the
correct specification prediluted coolant or
antifreeze concentrate. See Capacities and
Specifications (page 433).

Do not use the following as a coolant
substitute:
•

Alcohol.

•

Methanol.

•

Brine.

•

Any coolant mixed with alcohol or
methanol antifreeze.

Alcohol and other liquids can cause engine
damage from overheating or freezing.

Do not add extra inhibitors or non-specified
additives to the coolant. These can be
harmful and compromise the corrosion
protection of the coolant.

Engine and Secondary Cooling
System Refill Procedure

The following procedure should be used
when refilling the engine or secondary
cooling systems after it has been drained
or become extremely low:

1.

Before you remove the cap, turn the
engine off and let it cool.

2. When the engine is cool, wrap a thick

cloth around the cap. Slowly turn cap
counterclockwise until pressure begins
to release.

3. Step back while the pressure releases.

4. When you are sure that all the pressure

has been released, use the cloth to turn
it counterclockwise and remove the
cap.

5. Slowly add prediluted engine coolant

to the coolant reservoir until the
coolant level is within the minimum
and maximum range as listed on the
reservoir.

6. Reinstall the pressure relief cap.

7.

Start and run the engine at 2000 rpm
for 2 minutes.

8. Shut engine off, and remove the

pressure relief cap as previously
outlined.

9. If required, add prediluted engine

coolant to the coolant reservoir until
the coolant level is within the minimum
and maximum range as listed on the
reservoir.

10.

Engine cooling system: Repeat
Step 5 until the coolant level has
stabilized (is no longer dropping after
each step) and the upper radiator
hose at the radiator is warm to the
touch (indicating that the engine
thermostat is open and coolant is
flowing through the radiator).

11.

Check the secondary cooling system.
Repeat Step 5 until the coolant level
has stabilized (is no longer dropping
after each step) and the lower
passenger side of the secondary
radiator is warm to the touch
(indicating secondary thermostat is
open and coolant is flowing through
the entire system).

12.

Reinstall the pressure relief cap. Shut
the engine off and let it cool.

13.

Check the coolant level in the
reservoir before you drive your vehicle
the next few times.

14.

If necessary, add prediluted engine
coolant to the coolant reservoir until
the coolant level is within the
minimum and maximum range as
listed on the reservoir. After any
coolant has been added, check the
coolant concentration.

Recycled Coolant

We do not recommend the use of recycled
coolant as an approved recycling process
is not yet available.

Dispose of used engine coolant in an
appropriate manner. Follow your
community’s regulations and standards
for recycling and disposing of automotive
fluids.

Severe Climates

If you drive in extremely cold climates:
•

It may be necessary to increase the
coolant concentration above 50%.

•

A coolant concentration of 60%
provides improved freeze point
protection. Coolant concentrations
above 60% decrease the overheat
protection characteristics of the
coolant and may cause engine
damage.

If you drive in extremely hot climates:
•

You can decrease the coolant
concentration to 40%.

•

Coolant concentrations below 40%
decrease the freeze and corrosion
protection characteristics of the
coolant and may cause engine
damage.

Vehicles driven year-round in non-extreme
climates should use prediluted engine
coolant for optimum cooling system and
engine protection.

Checking Coolant Corrosion
Inhibitor Additive Strength

At specific mileage intervals as listed in the
scheduled maintenance information
chapter, the coolant corrosion inhibitor
additive should be checked. An information
message may display in the optional
information display at this time. The
purpose of checking is to verify the correct
engine coolant concentration (freeze point
protection) and corrosion inhibitor additive
level (strength) of the coolant for
maximum engine performance and
protection.

Three products are available to confirm
the life and health of the coolant, one tool,
a test kit and a coolant inhibitor additive:

•

Robinair® Coolant and Battery
Refractometer 75240 –
Recommended refractometer to test
coolant concentration. (Rotunda tool
part number: ROB75240).

•

Rotunda 328-R071–ELC (Antifreeze
Coolant ELC Contamination Kit) –
Evaluates the corrosion inhibitor
additive strength. Note the first step is
to verify the vehicle’s coolant
concentration is in the correct range of
40 – 60%. Coolant concentrations
outside this range will not provide valid
test results. If the report results in a
pass, for example the cooling system
does not show excessive
contamination, the corrosion inhibitor
additive strength is sufficient, and no
action is required. If the report results
as insufficient (does not pass), the
corrosion inhibitor additive strength of
the coolant is too low. If the engine
cooling system corrosion inhibitor
additive strength is low, add 47 fl oz
(1.4 L) of Motorcraft Specialty Orange
Engine Coolant Revitalizer. If the
secondary cooling system corrosion
inhibitor additive strength is low, add
16 fl oz (0.47 L) of Motorcraft Specialty
Orange Engine Coolant Revitalizer.

•

Motorcraft Specialty Orange Engine
Coolant Revitalizer – Additive to
boost the corrosion inhibitor level
based upon the test results of the
Antifreeze Coolant ELC Contamination
Kit. The Revitalizer may be added two
times over the life of the coolant. If
additional dosages are required, the
cooling system must be flushed and
refilled per the instructions in the
Workshop Manual.

Make sure to follow the proper coolant and
additive specifications. See Capacities
and Specifications (page 421).