How to Replace a Jeep TJ Dana 30 Pinion Seal

Oil leaking from the rear of the front differential around the drive shaft is a sure sign that the pinion seal needs replacing. This is a job that may look daunting at first, but if you have weekend mechanic skills, it's a project you can do, and you'll be able to keep some of your hard earned dollars in your pocket. It's important to replace the seal as soon as possible, because in addition to the oil leaking, dirt may also enter the differential through the bad seal.

Things You'll Need

  • Safety glasses
  • Gloves
  • Basic wrench set
  • 1-1/2-inch socket
  • Ratchet wrench
  • Gear puller
  • RTV sealant
  • Hammer
  • Flat-head screwdriver
  • Set the parking brake of the vehicle and properly chock the wheels. Put on protective eye wear and gloves, and remove the front drive shaft from the differential.

  • Using the 1-1/2-inch socket, remove the pinion nut from the center of the drive shaft yoke. Remove the nut and washer from the pinion shaft.

  • Use the gear puller to remove the yoke from the pinion shaft. Clean the rear of the yoke that inserts into the pinion area.

  • Install the sleeve onto the clean yoke using some RTV sealant and the included tool in the kit.

  • Remove the old seal from the differential by prying it out with a flat-head screwdriver and a hammer. Clean the opening in the differential where the seal sits.

  • Insert the new seal into the differential and lightly tap it into place until it is flush with the differential housing.

  • Reinstall the yoke onto the shaft and torque to 65 foot-pounds. Reinstall the drive shaft and check the differential oil level.