2021 FORD SUPER DUTY Owners Manual

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FORD SUPER DUTY 2021  Owners Manual Other Maintenance items
1
Change the automatic transmission fluid and filter. Consult
dealer for requirements.
Every 150,000 mi
(240,000 km) Replace the accessory drive belt or belts if not replaced
w

Page 578 of 666

FORD SUPER DUTY 2021  Owners Manual Towing a Trailer or Using a Car-top Carrier
Inspect and lubricate U-joints if equipped with grease
fittings.
Inspect frequently, service
as required
See axle maintenance items under Exceptions.
Inspec

Page 579 of 666

FORD SUPER DUTY 2021  Owners Manual Extensive Idling or Low-speed Driving for Long Distances, as in Heavy Commercial Use
(Such as Delivery, Taxi, Patrol Car or Livery)
Change engine oil and filter.
Every 5,000 mi (8,000 km)
or six month

Page 580 of 666

FORD SUPER DUTY 2021  Owners Manual Off-road operation
Inspect the wheels and related components for abnormal
noise, wear, looseness or drag.
Rotate tires, inspect tires for wear and measure tread
depth. 1
Replace front wheel bearing gr

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FORD SUPER DUTY 2021  Owners Manual Towing a Trailer or Using a Car-top Carrier
Inspect the engine and secondary cooling system coolant
concentration (freeze-point protection) and additive
(corrosion inhibitor) strength. If your vehicle

Page 582 of 666

FORD SUPER DUTY 2021  Owners Manual Frequent Low-speed Operation, Consistent Heavy Traffic Under 25 mph (40 km/h)  or
Long Rush-hour Traffic
Change the engine oil and filter as indicated by the
information display, and perform the servi

Page 583 of 666

FORD SUPER DUTY 2021  Owners Manual Sustained High-speed Driving at Gross Vehicle Weight Rating (Maximum Loaded Weight
for Vehicle Operation)
Inspect the engine and secondary cooling system coolant
concentration (freeze-point protection

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FORD SUPER DUTY 2021  Owners Manual Operating in Dusty or Sandy Conditions (Such as Unpaved or Dusty Roads)
Change the engine oil and filter. 2
Every 7,500 mi (12,000 km),
six months or 300 engine
hours
Inspect and lubricate the U-joint