Normal Vehicle Axle Maintenance

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.