TM-9-2330-335-14-P

SEMITRAILER, TACTICAL, BREAKBULK/CONTAINER TRANSPORTER, 22-1/2 TON, RESET M871R, M871A1R AND M871A2R

TECHNICAL MANUAL; FIELD AND SUSTAINMENT MAINTENANCE MANUAL (INCLUDES REPAIR PARTS AND SPECIAL TOOLS LIST)

SEPTEMBER 2008

TM-9-2330-335-14-P - Page 578 of 640

TM 9-2330-335-14&P

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NOTE

Brake drums should be replaced in pairs to achieve the same braking power on the axle.

Table 1. Troubleshooting Brake Drums.

EXAMPLE

PROBLEM

CAUSE

SOLUTION

Cracked brake

drum (new)

Cracked brake

drum (used)

Cracked brake

drum (used, low

mileage)

1 .

Misha

ndli

ng

2.

Heat checks

connect

together and

grow

through

drum section

3.

Improper

shoe contact

1.

Replace brake drum.

2.

Replace brake drum. Check brake balance, brake return

springs, brake adjustment, and lining type within vehicle

combination.

3.

Replace brake drum. Shoes must contact drum at the

center of the shoe.

Light heat check

Normal condition Does not impair brake performance. Brake drum may be

turned with normal limit. See maintenance instructions

regarding turning of brake surface.

Heavy heat check Imbalanced brake

system, dragged

brakes, or driver

abuse caused by

constant heating

and cooling of

brake surface.

Replace brake drum. Check brake balance, brake

return springs, brake adjustment, and lining type within

vehicle combination.

Fine grooves

Abrasive material

or poor quality

brake lining

Re-bore brake drum within normal limits or replace the drum

and lining. See maintenance instructions regarding turning of

brake surface.

Grooves

coinciding with

rivet holes

Loose rivets or

bolts or foreign

material

collecting in rivet

holes

Re-bore brake drums within normal limits or replace the

drum and lining. See maintenance instructions regarding

turning of brake surface.