TM    10-3930-643-34 FRONT AND REAR AXLES TROUBLESHOOTING AND MAINTENANCE. 7-1. Front  and  Rear  Axles  Troubleshooting. MALFUNCTION TEST  OR  INSPECTION CORRECTIVE  ACTION b. NOISE ON TURNS. Differential  side  gears  or  pinion  gears  defective. Contact  General  Support. c. NOISE WHILE VEHICLE IS COASTING. Defective  or  misadjusted  differential. Contact General Support. d. DIFFERENTIAL  OVERHEATS. Step 1. Check for correct lubricant level, refer to LO 10-3930-643-12. Step 2. Defective  differential,   refer to paragraph 7-4 for front and paragraph  7-8  for  rear  differential  replacement. e. LOSS OF LUBRICANT. Step 1. Check for correct level of lubricant, refer to LO 10-3930- 643-12. If lubricant level is correct, proceed to  Step 2. Step 2. Check for leaks. Leak at planetary cover gasket, refer to paragraph 7-5. Leak at differential, refer to paragraph 7-4 for front and paragraph 7-8 for rear. 7-3