2023 FORD SUPER DUTY Owners Manual

WHAT IS THE ELECTRONIC
LOCKING DIFFERENTIAL
The electronic locking differential is adevice housed in the rear axle and whenactivated, allows both wheels on that axleto turn at the same speed. The electroniclocking differential provides additionaltraction should your vehicle become stuck.
HOW DOES THE ELECTRONIC
LOCKING DIFFERENTIAL
WORK
You can activate the differentialelectronically and shift it on the fly withinthe operating speed range. The electronicdifferential disengages when the vehiclespeed exceeds a set value and it reengageswhen the vehicle speed drops below a setvalue. See Switching the ElectronicLocking Differential On and Off (page245). The electronic locking differentialcould engage based on certain selecteddrive modes. See Selecting a Drive Mode(page 311). The electronic lockingdifferential is for use in mud, rocks, sand,or any off-road condition where you needmaximum traction.
Note:The electronic locking differential isfor off-road use only and is not for use ondry pavement. Using the electronic lockingdifferential on dry pavement results inincreased tire wear, noise and vibration.
Note:The electronic locking differentialactivates or deactivates automaticallybased on speed, four-wheel drive mode, anddrive mode selection. See Switching theElectronic Locking Differential On andOff (page 245).
ELECTRONIC LOCKING
DIFFERENTIAL PRECAUTIONS
Operating the Electronic LockingDifferential with a Spare orMismatched Tires
On vehicles with an electronic lockingdifferential, the size of the spare tire canaffect performance of the system. If thereis a significant difference between the tworear tires, you may have limited electroniclocking differential functionality. If thesystem has difficulty disengaging, releasethe accelerator pedal and turn the steeringwheel in the opposite direction whenrolling. We recommend engaging anddisengaging the electronic lockingdifferential at a stop when you mount aspare on the rear axle.
SWITCHING THE ELECTRONIC
LOCKING DIFFERENTIAL ON
AND OFF - 4X4
Press the electronic lock differential switchto engage and disengage the lockingdifferential.
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4X4 Rear Electronic Locking Differential Engagement Speed and Availability
Automatic Re-Engagement SpeedAutomatic Disen-gagement SpeedMaximum Engage-ment SpeedDrive Modes
20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)Eco (2H, 4H)
20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)Tow/Haul Mode(2H,4H)
20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)Normal (2H, 4H)
20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)Slippery (2H, 4H)
No Speed LimitNo Speed LimitNo Speed LimitOff-Road (4H, 4L)1
No Speed LimitNo Speed LimitNo Speed LimitRock Crawl (4L)2
1 Engages when you select these drive modes. You have the ability to manually overridethe automatic engagement by pressing the electronic locking differential.2 Engages when you select these drive modes. You have the ability to manually overridethe automatic engagement by pressing the electronic locking differential. Only availablewith Tremor Package.
Automatic Re-Engagement SpeedAutomatic Disen-gagement SpeedMaximum Engage-ment Speed4WD Mode
No Speed LimitNo Speed LimitNo Speed LimitFour-Wheel DriveLow (4L)
Note:The electronic locking differentialmay not engage if you press the acceleratorpedal during an engagement attempt. Amessage could display in the instrumentcluster display guiding you to release theaccelerator pedal.
Note:Switching the electronic lockingdifferential off while turning results indisengagement difficulties. If the electroniclocking differential has difficultydisengaging, release the accelerator pedaland turn the steering wheel back and forthin small increments while maintainingcontrol and following a straight line.
Note:The electronic locking differential isfor off-road use only and is not for use ondry pavement. Using the electronic lockingdifferential on dry pavement results inincreased tire wear, noise and vibration.
Note:Do not perform this operation whencruise control or trail control is selected andactive. The system may not engage ordisengage as expected.
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SWITCHING THE ELECTRONIC
LOCKING DIFFERENTIAL ON
AND OFF - 4X2
Press the electronic locking differentialswitch to engage and disengage theelectronic locking differential.
4X2 Rear Electronic LockingDifferential Engagement Speed andAvailability
AutomaticRe-Engage-ment Speed
AutomaticDisengage-ment Speed
MaximumEngagementSpeed
20 mph(30 km/h)25 mph(41 km/h)20 mph(30 km/h)
Note:The electronic locking differential canactivate or deactivate automatically basedon speed, four-wheel drive mode, and drivemode selection. See Selecting a DriveMode (page 311).
Note:The electronic locking differentialmay not engage if you press the acceleratorpedal during an engagement attempt. Amessage could display in the instrumentcluster display guiding you to release theaccelerator pedal.
Note:Switching the electronic lockingdifferential off while turning results indisengagement difficulties. If the electroniclocking differential has difficultydisengaging, release the accelerator pedaland turn the steering wheel back and forthin small increments while maintainingcontrol and following a straight line.
Note:The electronic locking differential isfor off-road use only and is not for use ondry pavement. Using the electronic lockingdifferential on dry pavement results inincreased tire wear, noise and vibration.
Note: Do not perform this operation whencruise control or trail control is selected andactive. The system may not engage ordisengage as expected.
ELECTRONIC LOCKING
DIFFERENTIAL INDICATORS
If both rear wheel axle shaftslock together, the indicator in thecluster is amber, providingadditional traction.
If you select the electronic lockingdifferential and the indicator in the clusteris gray or turns from amber to gray whiledriving, one of the following has occurred:
•The vehicle speed is too high.
•The accelerator pedal is too high duringan engagement attempt.
•The vehicle is experiencing an anti-lockbrake activation.
•The left and right wheel speeddifference is too high during anengagement attempt.
If you select the electronic lockingdifferential and the indicator in the clusterdoes not turn on, the following hasoccurred:
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•The system has malfunctioned andaccompanies a check lockingdifferential message in the informationdisplay. See your dealer as soon aspossible.
Note:If the vehicle is experiencing ananti-lock braking event, the electroniclocking differential may momentarilydisengage.
ELECTRONIC LOCKING DIFFERENTIAL – TROUBLESHOOTING
ELECTRONIC LOCKING DIFFERENTIAL – INFORMATION MESSAGES
Description and ActionMessage
An electronic locking differential system fault is present.Contact an authorized dealer as soon as possible.Check Locking Differen-tial
Release the accelerator pedal to engage.To Engage LockingDifferential ReleaseAccelerator Pedal
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BRAKE PRECAUTIONS
Wet brakes result in reduced brakingefficiency. Gently press the brake pedal afew times when leaving a car wash ordriving from standing water to dry thebrakes.
Note:Depending on applicable laws andregulations in the country where your vehiclewas originally built, the stoplamps couldflash during heavy braking. The hazardwarning flashers could also turn on whenyour vehicle comes to a stop.
ANTI-LOCK BRAKING SYSTEM
ANTI-LOCK BRAKING SYSTEMLIMITATIONS
The anti-lock braking system does noteliminate the risk of crash when:
•You drive too closely to the vehicle infront of you.
•Your vehicle is hydroplaning.
•You take corners too fast.
•The road surface is poor.
Note: If the system activates, the brakepedal could pulse and travel further.Maintain pressure on the brake pedal.
BRAKE OVER ACCELERATOR
In the event the accelerator pedalbecomes stuck or entrapped, apply steadyand firm pressure to the brake pedal toslow the vehicle and reduce engine power.If you experience this condition, apply thebrakes and bring your vehicle to a safestop. Move the transmission to park (P),switch the engine off and apply the parkingbrake. Inspect the accelerator pedal forany interference. If none are found and thecondition persists, have your vehicle towedto the nearest authorized dealer.
LOCATING THE BRAKE FLUID
RESERVOIR
See Under Hood Overview (page 441).
CHECKING THE BRAKE FLUID
WARNING: Do not use any fluidother than the recommended brake fluidas this will reduce brake efficiency. Useof incorrect fluid could result in the lossof vehicle control, serious personal injuryor death.
WARNING: Only use brake fluidfrom a sealed container. Contaminationwith dirt, water, petroleum products orother materials may result in brakesystem damage or failure. Failure toadhere to this warning could result in theloss of vehicle control, serious personalinjury or death.
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: The brake systemcould be affected if the brake fluid levelis below the MIN mark or above the MAXmark on the brake fluid reservoir.
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1.Park your vehicle on a level surface.
2.Look at the brake fluid reservoir to seewhere the brake fluid level is relativeto the MIN and the MAX marks on thereservoir.
Note:To avoid fluid contamination, thereservoir cap must remain in place and fullytight, unless you are adding fluid.
Only use fluid that meets ourspecifications. See Capacities andSpecifications (page 520).
BRAKE FLUID SPECIFICATION
See Brake Fluid Specification (page 539).
BRAKES –
TROUBLESHOOTING
BRAKES – WARNING LAMPS
WARNING: Driving your vehiclewith the warning lamp on is dangerous.A significant decrease in brakingperformance may occur. It may take youlonger to stop your vehicle. Have yourvehicle checked as soon as possible.Driving extended distances with theparking brake engaged can cause brakefailure and the risk of personal injury.
If the ABS indicator illuminateswhen you are driving, thisindicates a malfunction. Yourvehicle continues to have normal brakingwithout the anti-lock braking systemfunction. See an authorized dealer.
It also momentarily illuminates when youswitch the ignition on to confirm the lampis functional. If it does not illuminate whenyou switch the ignition on, or begins toflash at any time, have the system checkedby an authorized dealer.
The brake indicator momentarilyilluminates when you switch theignition on to confirm the lampis functional. It may also illuminate whenyou apply the parking brake and theignition is on. If it illuminates when yourvehicle is moving, make sure the parkingbrake is disengaged. If the parking brakeis disengaged, this indicates low brake fluidlevel or a brake system fault. See anauthorized dealer.
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BRAKES – INFORMATION MESSAGES
DetailsMessage
The brake fluid level is low, check the brake system immedi-ately. See Checking the Brake Fluid (page 249).Brake Fluid Level Low
Have the system checked as soon as possible.Check Brake System
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BRAKES – FREQUENTLY ASKEDQUESTIONS
Is it normal for my brakes to makenoise?
Occasional brake noise is normal. If ametal-to-metal, continuous grinding, orsqueal sound is present, the brake liningcould be worn. Have the system checked.
There is an electrical motor soundwhen I press on the brake pedal oractivate the park brake switch. Isthis normal?
Yes, those sounds are the electronic brakebooster or the electronic park brakeoperating.
Note: Brake dust could accumulate on thewheels, even under normal drivingconditions. Some dust is normal as thebrakes wear and does not contribute tobrake noise. See Cleaning Wheels (page?).
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