Merchant Automotive Transfer Case Speed Sensor O-ring, Duramax | 1998 - 2007
This O-ring seal is used to seal the speed sensor on the transfer case. The seal should be replaced each time the speed sensor is removed from the transfer case to prevent leaks. It is located along the tailshaft at around the 11 o'clock position.
NOTE: NP246 transfer cases use three speed sensors for automatic four wheel drive engagement so if you are servicing all three speed sensors you will need three O-ring seals.