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Transfer Case Speed Sensor O-ring | 1998-2007

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Product Information

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.

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.


Click here to view the Merchant Automotive Transfer Case Pump Upgrade kit.


Click here to view transfer case pump upgrade installation instructions.


Click here to view the Truck U segment on the Merchant Automotive Transfer Case Pump Upgrade.



My transfer case was dry or way less than 2 quarts of fluid came out when I drained it. My output shaft seals and the speed sensor seal look good and show no signs of leaking, what could be the problem?

With a 1998 through early-2007 transfer case, pump rub is the likely problem. Click here to view the Merchant Automotive video on pump rub and our permanent solution to the problem.