TM  10-3930-643-34 FRONT  AND  REAR  AXLES  TROUBLESHOOTING  AND  MAINTENANCE.  (cont) 7 - 1 . Front  and  Rear  Axles  Troubleshooting.  (cont) MALFUNCTION TEST  OR  INSPECTION CORRECTIVE  ACTION e. LOSS OF LUBRICANT. (cont) If leak is at differential drive yoke, contact General Support. If no external leaks exist, proceed to Step 3. Step 3. Check for oil behind wheel in brake compartments. If oil is leaking into brake compartment, replace axle spindle housing oil seal, refer to paragraph 7-5. f. DIFFERENTIAL OIL LEVEL RISES. Replace drive axle oil seal, refer to paragraph 7-5. 7-4