TM-9-2320-285-24-1

TRUCK TRACTOR, YARD TYPE, 43,500 LB GVW, DED, 4X2, ARMY MODEL M878A1

TECHNICAL MANUAL; ORGANIZATIONAL, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL

OCTOBER 1985

TM-9-2320-285-24-1 - Page 552 of 987

TM 9-2320-285-24-1

2-46.

SERVICE BRAKE SYSTEM TROUBLESHOOTING (CONT)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

10. REAR AXLE BRAKES LININGS WEAR UNEVENLY (Cont)

Step 2.

Remove brake shoe and lining assemblies (para 2-50b) and check brake return springs for proper

tension: spring tension shall be 75-90 pounds pull at 9-1/2 inches.

a.

If return springs do not have proper tension, replace (para 2-50b).

b.

If return springs have proper tension, go to step 3 below.

Step 3.

Check that spring pins are not damaged or broken.

a.

If spring pins are damaged or broken, replace (para 2-50b).

b.

If spring pins are okay, refer to Malfunction 3, step 4, above.

11. FRONT AXLE BRAKES FROZEN OR LOCKED

Step 1.

Remove brake drums (para 2-44a).

Disassemble front brakes (para 2-50a) and check plungers for damage.

a.

If plungers are damaged, replace (para 2-50a).

b.

If plungers are not damaged, go to step 2 below.

Step 2.

Check front axle brakes air chambers for damage.

a.

If front axle brakes air chambers are damaged, repair (para 2-51d(1)).

12. REAR AXLE BRAKES FROZEN OR LOCKED

Step 1.

Check air brake system lines and fittings for air leaks.

a.

If lines are leaking air, repair or replace (para 2-51a).

b.

If fittings are leaking air, tighten.

If fitting leaks after tightening, replace (para 2-51a).

c.

If air leaks are not found, go to step 2 below.

Step 2.

Check rear axle brakes air chambers for damage.

a.

If damage is found, repair (para 2-51d(2)).

b.

If damage is not found, go to step 3 below.

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