Normal Vehicle Axle Maintenance

Rear axles and transfer case/power transfer unit ( PTU ) units containing synthetic lubricant and light duty trucks equipped with Ford-design axles are lubricated for life. These lubricants are not to be checked or changed unless service is required, or if a leak is suspected or the axle assembly has been submerged in water.

The axle and transfer case/PTU fluid should be changed anytime they have been submerged in water. Non-synthetic rear axle lubricants should be installed new every 4,800 km ( 3,000 mi ) or 3 months, whichever occurs first, during extended trailer tow operation above 21 ° C ( 70 ° F ) ambient and wide open throttle ( WOT ) for extended periods above 72 km/h ( 45 mph ).

The 3,000 mile lube change interval may be waived if the axle was filled with 75W-140 synthetic gear lubricant. Add 4 ounces of additive friction modifier for complete refill of Traction-Lok rear axles.

The axle lubricant should be changed anytime an axle has been submerged in water.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Normal Vehicle Axle Maintenance

Use the Manual With the Right Hardware

When to See a Mechanic

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