TM10-3930-660-20 Table 2-3. Mechanical Troubleshooting (Cont’d) MALFUNCTION TEST OR INSPECTION CORRECTIVE  ACTION Step 2. Check for foaming transmission oil. Refer to Test 29, Loss of Power, in this table. AXLES AND DIFFERENTIALS 34. CONTINUOUS “CLICKING" SOUND  FROM FRONT AXLE WHEN MOVING IN  A STRAIGNT LINE Check for incorrect front tires and/or unequal diameters of front  tires. Replace tire(s) or adjust tire pressures until both tire diameters are the same, para. 13-4. 35. SLOW  ENGAGENENT OF FRONT NO SPIN DIFFERENTIAL CLUTCH ASSEMBLIES Step 1. Inspect axle housing for contamination in oil. Clean if necessary, para. 11-3. Step 2. Heavy gear lubricant. Change to appropriate lubricant, para. 11-3. 36. PARK BRAKE WILL NOT HOLD UNIT Step 1. Check park brake cable for proper  adjustment. Readjust as necessary, para.  12-4. Step 2. Inspect park brake drum lining. Replace if worn or glazed, para. 12-3. Step 3. Check for missing or damaged park brake linkage. Replace if necessary para. 12-4. 2-43