TM-9-2320-272-24-3

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL; VOLUME 3 OF 4

JUNE 1998

TM-9-2320-272-24-3 - Page 606 of 799

4-181. REAR

TM 9-2320-272-24-3

1.

Clean and inspect all thrust washers (1) for cracks and measure thickness. Replace if cracked or if

thickness is less than 0.059 in. (1.50 mm).

2.

Clean drum shaft (3) for cracks, chips, straightness, and wear. Roll drum shaft (2) on a flat surface

to check wear. Measure bearing surfaces for wear with a micrometer. Replace if cracked, chipped,

bent, or any bearing surface is less than 2.995 in. (76.07 mm) in diameter.

3.

Clean and inspect three bushings (3), one in end frame and two in drum, for cracks, chips, scoring,

and wear. Measure wear with an inside micrometer. Replace bushings (3) if cracked, chipped,

scored, or inner diameter is more than 3.010 in. (76.45 mm).

4.

Clean and inspect worm shaft (4) and worm gear (5) for cracks, chips, scoring, or damaged bearings.

Replace if cracked, chipped, scored or if balls, rollers, or cage is damaged.

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