4-53. REAR AXLE REPLACEMENT (Con't).
Open pressure tank draincock (4) to relieve air pressure.
Use a drain pan to catch any draining brake fluid. Cleanup all spills.
Disconnect hydraulic brake hose (3) from multiple connector (11).
Disconnect each tube assembly (9) from multiple connector (11 ) and tee (6) on backing plate (5),
Remove ten locknuts (8) and screws (7) securing each backing plate (5) to axle (1 O). Remove backing plates.
Remove two wiper rings (16) from axle if they are badly worn or damaged.
Axle is heavy and awkward to handle. Use caution, provide adequate support, and use
assistance during removal. Failure to follow this warning may result in serious injury to
Support axle (10) at each end with a floor jack.
Remove eight nuts (2), Iockwashers (l), and four U-bolts (12). Discard Iockwashers.
Lower axle (1 O) and remove from under semitrailer.
CLEANING AND INSPECTION
Remove mud and dirt from all exposed surfaces using water.
Dry cleaning solvent, P-D-680, is toxic and flammable. Always wear protective goggles
and gloves, and use only in a well-ventilated area. Avoid contact with skin, eyes, and
clothes, and DO NOT breathe vapors. DO NOT use near open flame or excessive heat.
The solvent's flash point Is 100F-138F (38C-59C). If you become dizzy while
using cleaning solvent, Immediately get fresh air and medical help. If solvent contacts
eyes, immediately wash your eyes and get medical aid.
Remove grease from spindles and wheel retaining parts using dry cleaning solvent.
Check bearing seats for roughness or damage. File any spots, burrs, or roughness.
Check threads of axle spindIes for wear, cross threads, or damage. Remove burrs or hand chase threads using
a fine file.
Check axle spindles for bends. Indication of a bent axle spindle is binding bearings that cannot be adjusted
properly and that cause extremely uneven wear of brakeshoe linings.
If axle is bent, cracked, or otherwise unserviceable, replace with a new axle.
If installing new axle, use old axle as a guide and weld screw (14) and two straps (13) to axle.