a. Remo val of Brake Drum and Hub From Axle. Jack wheels clear of ground and remove wheels from
hub (fig. 4-24); then remove brake drum and hub from axle by following procedures shown in steps 1 thru 7
b. Removal of Brake Drum From Hub.
(2) Remove brake drum from hub by following procedures shown on figure 4-28.
c. Removal of Bearing Cup From Hub.
(1) With hub removed from brake drum (fig. 4-27), place hub on blocks; then drive bearing cup from
(2) Turn hub over and repeat the process to remove the opposite cup.
d. Cleaning, Inspection and Repair.
Cleaning solvent (Fed Spec PD-680) is both toxic and flammable. Avoid
prolonged breathing of vapors. Avoid skin contact. Use only in well-ventilated
area. Keep away from open flame.
(1) Cleaning. Wash hub, brake drum, and bearings thoroughly with dry-cleaning solvent (PD-680)
(2) Inspection and repair.
(a) Hubs. Inspect hub and adapter carefully for cracks and other damage. Inspect bearing cups
for cracks, chipped spots, or wear caused by contact with bearing rollers. Make sure cups fit
tightly in hub. If cups are damaged or worn, replace. Oil the bearing cones and rollers lightly
and rotate by hand to test for tightness. Replace if there is evidence of scoring, pitting, or
wear. Inspect oil seals to make sure contact materiel is intact and pliable. Inspect threads on
wheel studs, capnuts, and wheel nuts; replace if stripped or damaged.
(b) Brake drums. Inspect brake drum for warpage, cracks, or scored braking surfaces. Replace
drum if cracked or deformed. If scored, notify Direct Support maintenance.
e. Installation of Bearing Cup in Hub.
(1) With hub placed on a solid surface, position cup over cup seat and press into place. Make certain
the cup is fully seated.
(2) Turn hub over and repeat procedure for opposite cup.