The transfer case is the mechanical unit that splits power between the front and rear axles. It receives power from the transmission or transaxle output shaft. Lubricant Leakage: a loss of lubricating fluid from the housing, gaskets, or seals. Leaks may be noticed as oil drips on the pavement. Failure to Engage Properly: The transfer case fails in only one gear: possible cause of defective internal parts or linkage. The vehicle will not move at all in all gears: possible cause of defective stripped gears or splines, a broken chain, a broken shaft. Abnormal Noises: During vehicle operation, abnormal noises including whines and rumbles occur in the transfer case. Other types of noises can be grinding, knocking, popping, or snapping sounds. Hard Shifting: In some cases, it may become difficult to change transfer case gears. Possible cause: a shift linkage that is bent or worn.