Rear axle noises heard on drive will usually be heard also on coasting, although  not as loud. 
 | Adjust or replace the differential drive pinion gear and the ring gear set. 
|     •  | For Spicer Eaton axles, call 1-800-TCM-HELP |  
  
|     •  | For Meritor axles, call 1-800-535-5560 |  
  
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Differential drive pinion gear and ring gear too tight audible when slowing down and disappears when  driving. 
 | Adjust the differential drive pinion gear to the ring gear backlash. 
|     •  | For Spicer Eaton axles, call 1-800-TCM-HELP |  
  
|     •  | For Meritor axles, call 1-800-535-5560 |  
  
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