Off-road operation
Inspect the wheels and related components for abnormalnoise, wear, looseness or drag.
Rotate tires*, inspect tires for wear and measure treaddepth.
Replace front wheel bearing grease and grease seals ifnon-sealed bearings are used.Every 30000 miles (48000km)
Change rear axle fluid (F-450 and F-550 only).Every 50000 miles (80000km)
Change transfer case fluid (Four-wheel drive vehicles).Every 60000 miles (96000km)
*Vehicles with dual rear wheels should rotate the front wheels when specified; rear wheelsonly if unusual wear is noted.
Exclusive use of E85 (Flex fuel vehicles only)
If ran exclusively on E85, fill the fuel tank full with regularunleaded fuel.Every oil change interval
6.7L Diesel Engine
See the diesel supplement for specialoperating condition information.
Exceptions
There are several exceptions to the NormalSchedule:
Normal vehicle axle maintenance: Rearaxles and power take-off units withsynthetic fluid and light-duty trucksequipped with Ford-design axles arelubricated for life; do not check or changefluid unless a leak is suspected, service isrequired or the assembly has beensubmerged in water. During long periodsof trailer towing with outside temperaturesabove 70°F (21°C) and at wide-openthrottle for long periods above 45 mph (72km/h), change non-synthetic rear axle fluidevery 3000 miles (4800 kilometers) or
three months, whichever comes first. Thisinterval can be waived if the axle is filledwith 75W140 synthetic gear fluid meetingFord specification WSL-M2C192-A, partnumber F1TZ-19580-B, or equivalent. Addfriction modifier XL-3 (EST-M2C118-A) orequivalent for complete refill ofTraction-Lok rear axles.  See Capacitiesand Specifications (page 292).
Police, Taxi and Livery vehicle axlemaintenance: Change rear axle fluid every100000 miles (160000 kilometers). Rearaxle fluid change may be waived if the axlewas filled with 75W140 synthetic gear fluidmeeting Ford specificationWSL-M2C192-A, part numberF1TZ-19580-B, or equivalent. Add fourounces (118 milliliters) of additive frictionmodifier XL-3 (EST-M2C118-A), orequivalent, for complete refill ofTraction-Lok rear axles. Change the axlefluid anytime the axle submerges in water.
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Super Duty (TFA)
Scheduled Maintenance