2023 FORD SUPER DUTY cooling

We recommend the use of a wheel lift anddollies or flatbed equipment to tow yourvehicle. Vehicle damage could occur iftowed incorrectly, or by any other means.
Front-wheel and rear-wheel drive vehiclesmust have their designated drive wheelsoff the ground regardless of towingdirection. Use tow dollies to preventdamage to the transmission.
All-wheel or four-wheel drive vehiclesrequire that all wheels be off the groundusing a wheel lift and dollies or flatbedequipment. This prevents damage to thetransmission and drive system.
Note:You need to switch on the ignition tounlock the steering.
Note:Make sure you check the steeringcolumn before towing. It could lock if thebattery is dead.
FAIL-SAFE COOLING
WHAT IS FAIL-SAFE COOLING
Fail-safe cooling allows you to temporarilydrive your vehicle before any incrementalcomponent damage occurs due tooverheating.
The fail-safe distance depends on outsidetemperature, vehicle load and terrain.
HOW DOES FAIL-SAFE COOLINGWORK
If the engine reaches a presetover-temperature condition, the engineautomatically switches to alternatingcylinder operation. Each disabled cylinderacts as an air pump and cools the engine.
When this occurs, your vehicle stilloperates, however:
•Engine power is limited.
•The air conditioning system turns off.
Continued operation increases the enginetemperature, causing the engine tocompletely shut down. Your steering andbraking effort increases in this situation.
When the engine temperature cools, youcan re-start the engine.
Note:Have your vehicle checked as soonas possible to minimize engine damage.
DRIVING WHEN FAIL-SAFE MODEIS ACTIVATED
WARNING: Fail-safe mode is foruse during emergencies only. Operateyour vehicle in fail-safe mode only aslong as necessary to bring your vehicleto rest in a safe location and seekimmediate repairs. When in fail-safemode, your vehicle will have limitedpower, will not be able to maintainhigh-speed operation, and maycompletely shut down without warning,potentially losing engine power, powersteering assist, and power brake assist,which may increase the possibility of acrash resulting in serious injury.
WARNING: Do not remove thecoolant reservoir cap when the engine ison or the cooling system is hot. Wait 10minutes for the cooling system to cooldown. Cover the coolant reservoir capwith a thick cloth to prevent thepossibility of scalding and slowly removethe cap. Failure to follow this instructioncould result in personal injury.
Continued operation increases the enginetemperature, causing the engine tocompletely shut down. Your steering andbraking effort increases in this situation.
When the engine temperature cools, youcan re-start the engine. Have your vehiclechecked as soon as possible to minimizeengine damage.
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Your vehicle has limited engine powerwhen in the fail-safe mode, drive yourvehicle with caution. Your vehicle does notmaintain high-speed operation and theengine may operate poorly.
Remember that the engine is capable ofautomatically shutting down to preventengine damage. In this situation:
1.Pull off the road as soon as safelypossible and switch the engine off.
2.If you are a member of a roadsideassistance program, we recommendthat you contact your roadsideassistance service provider.
3.If this is not possible, wait for a shortperiod of time for the engine to cool.
4.Check the coolant level. If the coolantlevel is at or below the minimum mark,add prediluted coolant immediately.
5.When the engine temperature cools,you can re-start the engine. Have yourvehicle checked as soon as possible tominimize engine damage.
Note:Driving your vehicle without repairincreases the chance of engine damage.
FAIL-SAFE COOLING INDICATORS
If the engine begins to overheat,the coolant temperature gaugemoves toward the red zone.
A warning lamp illuminates anda message may appear in theinstrument cluster display.
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IDENTIFYING THE FUSES IN THE UNDER HOOD FUSE BOX
Protected ComponentRatingItem
Cooling fan 1.50 A1
Heater.50 A2
Heater.50 A3
Heater.50 A4
Four-wheel drive module.30 A9
Compressed natural gasmodule switch.30 A10
Anti-lock brake systempump.60 A12
Passenger power seat.30 A13
Anti-lock brake systemvalve.40 A14
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UNDER HOOD OVERVIEW - 6.7L DIESEL
Battery. See Changing the 12V Battery (page 457).A
Under hood fuse box. See Accessing the Under Hood Fuse Box (page 430).B
Engine oil dipstick. See Engine Oil Dipstick Overview (page 444).C
Secondary fuel filter. See Changing the Fuel Filter (page 453).D
Engine oil filler cap. See Checking the Engine Oil Level (page 444).E
Engine cooling system coolant reservoir - primary high-temperature coolingsystem. See Checking the Coolant Level (page 450).F
Brake fluid reservoir. See Checking the Brake Fluid (page 249).G
Battery. See Changing the 12V Battery (page 457).H
Windshield washer fluid reservoir. See Adding Washer Fluid (page 115).I
Power steering fluid reservoir. See Checking the Hydraulic Power SteeringFluid (page 280).J
Secondary cooling system coolant reservoir. See Checking the Coolant Level(page 450).K
Air filter assembly. See Changing the Engine Air Filter (page 445).L
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COOLANT
CHECKING THE COOLANT LEVEL
WARNING: Do not remove thecoolant reservoir cap when the engine ison or the cooling system is hot. Wait 10minutes for the cooling system to cooldown. Cover the coolant reservoir capwith a thick cloth to prevent thepossibility of scalding and slowly removethe cap. Failure to follow this instructioncould result in personal injury.
WARNING: To reduce the risk ofpersonal injury, make sure the engine iscool before unscrewing the coolantpressure relief cap. The cooling systemis under pressure. Steam and hot liquidcan come out forcefully when you loosenthe cap slightly.
When the engine is cold, check theconcentration and level of the coolant atthe intervals listed in the scheduledmaintenance information. See ScheduledMaintenance (page 591).
Note:Make sure that the coolant level isbetween the MIN and the MAX marks onthe coolant reservoir.
Note: Coolant expands when it is hot. Thelevel may extend beyond the MAX mark.This is normal.
Maintain coolant concentration within48% to 50%, which equates to a freezepoint between -29°F (-34°C) and -35°F(-37°C). Coolant concentration should bechecked using a refractometer. We do notrecommend the use of hydrometers orcoolant test strips for measuring coolantconcentration.
ADDING COOLANT
WARNING: Do not add coolantwhen the vehicle is on or the coolingsystem is hot. Failure to follow thisinstruction could result in personal injury.
WARNING: Do not remove thecoolant reservoir cap when the engine ison or the cooling system is hot. Wait 10minutes for the cooling system to cooldown. Cover the coolant reservoir capwith a thick cloth to prevent thepossibility of scalding and slowly removethe cap. Failure to follow this instructioncould result in personal injury.
WARNING: Do not allow the fluidto touch your skin or eyes. If thishappens, rinse the affected areasimmediately with plenty of water andcontact your physician.
WARNING: Do not put coolant inthe windshield washer reservoir. Ifsprayed on the windshield, coolant couldmake it difficult to see through thewindshield.
WARNING: Do not add coolantfurther than the MAX mark.
Note: Do not use stop leak pellets, coolingsystem sealants, or non-specified additivesas they can cause damage to the enginecooling or heating systems. Resultingcomponent damage may not be covered bythe vehicle Warranty.
Note:Automotive fluids are notinterchangeable.
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It is very important to use predilutedcoolant approved to the correctspecification in order to avoid plugging thesmall passageways in the engine coolingsystem. See Capacities andSpecifications (page 520). Do not mixdifferent colors or types of coolant in yourvehicle. Mixing of engine coolants or usingan incorrect coolant may harm the engineor cooling system components and maynot be covered by the vehicle Warranty.
Note:If prediluted coolant is not available,use the approved concentrated coolantdiluting it to 50/50 with deionised ordistilled water. See Capacities andSpecifications (page 520). Using water thathas not been deionised may contribute todeposit formation, corrosion and pluggingof the small cooling system passageways.
Note: Coolants marketed for all makes andmodels may not be approved to ourspecifications and may cause damage tothe cooling system. Resulting componentdamage may not be covered by the vehicleWarranty.
If the coolant level is at or below theminimum mark, add prediluted coolantimmediately.
To top up the coolant level do thefollowing:
1.Unscrew the cap slowly. Any pressureescapes as you unscrew the cap.
2.Add prediluted coolant approved tothe correct specification. SeeCapacities and Specifications (page520).
3.Add enough prediluted coolant toreach the correct level.
4.Replace the coolant reservoir cap. Turnthe cap clockwise until it contacts thehard stop.
5.Check the coolant level in the coolantreservoir the next few times you driveyour vehicle. If necessary, add enoughprediluted engine coolant to bring thecoolant level to the correct level.
If you have to add more than 1.1 qt (1 L) ofengine coolant per month, have yourvehicle checked as soon as possible.Operating an engine with a low level ofcoolant can result in engine overheatingand possible engine damage.
In case of emergency, you can add a largeamount of water without engine coolantin order to reach a vehicle service location.
Water alone, without engine coolant, cancause engine damage from corrosion,overheating or freezing.
Do not use the following as a coolantsubstitute:
•Alcohol.
•Methanol.
•Brine.
•Any coolant mixed with alcohol ormethanol antifreeze.
Alcohol and other liquids can cause enginedamage from overheating or freezing.
Do not add extra inhibitors or additives tothe coolant. These can be harmful andcompromise the corrosion protection ofthe coolant.
CHANGING THE COOLANT
For coolant change, see your authorizeddealer.
Changing the coolant is necessary atspecific mileage intervals listed in thescheduled maintenance information. SeeScheduled Maintenance (page 591).
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MANAGING THE COOLANTTEMPERATURE
If you tow a trailer with your vehicle, theengine may temporarily reach a highertemperature during severe operatingconditions, for example ascending a longor steep grade in high ambienttemperatures.
At this time, you may notice the coolanttemperature gauge moves toward the redzone and a message may appear in theinformation display.
WARNING: To reduce the risk ofcrash and injury, be prepared that thevehicle speed may reduce and thevehicle may not be able to acceleratewith full power until the coolanttemperature reduces.
WARNING: If you continue to driveyour vehicle when the engine isoverheating, the engine could stopwithout warning. Failure to follow thisinstruction could result in the loss ofcontrol of your vehicle.
You may notice a reduction in vehiclespeed caused by reduced engine power inorder to manage the engine coolanttemperature. Your vehicle may enter thismode if certain high-temperature andhigh-load conditions take place. Theamount of speed reduction depends onvehicle loading, grade and outsidetemperature. If this occurs, there is noneed to stop your vehicle. You cancontinue to drive. See Fail-Safe Cooling(page 425).
The air conditioning may automaticallyturn on and off during severe operatingconditions to protect the engine fromoverheating. When the coolanttemperature decreases to the normaloperating temperature, the air conditioningturns on.
If the coolant temperature gauge movesfully into the red zone, or if the coolanttemperature warning or service enginesoon messages appear in your informationdisplay, do the following:
1.Stop your vehicle as soon as it is safeto do so. Fully apply the parking brake,shift into park (P) or neutral (N).
2.Leave the engine running until thecoolant temperature gauge needlereturns to the normal position. If thetemperature does not drop afterseveral minutes, follow the remainingsteps.
3.Switch the engine off and wait for it tocool. Check the coolant level.
4.If the coolant level is at or below theminimum mark, add prediluted coolantimmediately.
5.If the coolant level is normal, restartthe engine and continue.
COOLANT – WARNING LAMPS
If the engine begins to overheat,the coolant temperature gaugemoves toward the red zone.
A warning lamp illuminates anda message may appear in theinformation display.
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Note:If you use your vehicle regularly abovethe altitude of 5,000 ft (1,524 m) and underthe temperature of -4.0°F (-20°C), it isrecommended to use the alternative engineoil.
COOLING SYSTEM CAPACITY
AND SPECIFICATION - 6.7L
DIESEL
Use coolant that meets the definedspecification.
If you do not use coolant that meets thedefined specification, it could result in:
•Component damage that your vehiclewarranty does not cover.
•Reduced vehicle performance.
Note:An engine block heater isrecommended at temperatures below-9°F(-23°C).
Capacities
QuantityVariant
31.7 qt (30 L)Primary cooling system.
33.3 qt (31.5 L)Primary cooling system with auxiliary radi-ator.
8.2 qt (7.8 L)Secondary cooling system with ureainjector cooling.
10.0 qt (9.5 L)Secondary cooling system with ureainjector cooling and cooled compressor.
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