Section 05-00: Axle and Driveshaft, Service | 1996 F-150, F-250, F-350 4x2 and 4x4, F-Super Duty and Bronco Workshop Manual |
Ford Rear Axle
The filler hole is in the differential carrier casting. Fill F-150 rear axles (4001) 6.35-14.28mm (1/4 to 9/16 inch) below bottom of the hole.
NOTE: To check F-250 and F350 rear axles for proper lubricant level, the filler plug should be backed out slowly. If seepage occurs around the threads of the plug, immediately turn the plug back in to avoid any drainage. This condition indicates that the specified factory fill amount of lubricant is in the rear axle.
Service fill for F-250 and F-350 with Ford axles is level with bottom of filler hole.
Dana Rear Axles
Dana rear axles do not have a drain plug. The axle housing cover (4033) should be loosened and removed from the axle housing to allow drainage. The RTV sealer must be removed from the axle housing cover and axle housing. Reseal with Silicone Rubber F4AZ-19562-B or equivalent meeting Ford specification WSE-M4G323-A1.
NOTE: A suction pump may also be used for draining lube from the axle housing. Note that this method will not clean all debris which may settle at the bottom of the carrier.
Dana Front and Rear Axles
The lubricant level in these axles may vary depending on internal casting variations, spring orientation, or flatness of the floor or hoist involved, as well as the amount of fill. During manufacture, axles are filled by volume, not to a specific level. Dealer inspection of rear axle lubricant level is not an authorized element of vehicle preparation. The only times a dealer should check lubricant levels are when a leak is suspected or observed or when an axle repair requires draining and refilling.
These Dana rear axles have a proper lubricant fill level of 6.35-19.05mm (1/4-3/4 inch) below the bottom of the fill hole in the axle housing cover. Dealers should avoid overfilling the rear axle above this range because overfilling can cause foaming and raise the temperature of the lubricant, leading to lubricant oxidation and eventual gear or bearing failure in extreme cases. The extra lubricant may also be expelled through the rear axle vent hose.