Last Revised: 10SE2007

REPLACING POWER STEERING GEAR PITMAN SHAFT SEALS

WITH THE GEAR STILL IN THE CAR

The Chevrolet shop manual gives some tips on how to replace the pitman shaft seals with the gear still in the car.

  1. Remove the pitman nut and lockwasher. Remove the pitman arm with a heavy duty puller.
  1. Thoroughly clean the end of the pitman shaft and gear housing.
  1. Remove the snap ring.
  1. Screw the pitman shaft nut back onto the pitman shaft. Now when you blow the seals out of the gear housing they will be retained on the pitman shaft. Now you can take them off the shaft one at a time and note exactly what order and the orientation of the original parts.
  1. Place a large container under the pitman shaft, start the engine, and turn the steering wheel all the way to full left lock so that the oil pressure in the gear will force the pitman shaft seals out. Bump the steering into full left lock. Do not hold at full lock for more that a couple seconds at a time.
  1. Remove the nut and inspect the seals for damage to the rubber covering on the O.D. If the O.D. appears scored, inspect the housing for burrs and remove them. Check the sealing surface of the pitman shaft for roughness or pitting. You should try to smooth out any corrosion or minor pitting with sandpaper or crocus cloth. If it is seriously pitted, replacement of the pitman shaft is recommended.
  1. Clean the end of the housing thoroughly so that dirt will not enter the housing with the installation of the new seals.
  1. Tape the splines on the end of the pitman shaft to insure that the seals will not be cut during assembly. Note: Only one layer of tape should be used. An excessive amount of tape will not allow the seals to pass over it, due to the close tolerance between the seals and the pitman shaft.
  1. I always recommend that you use genuine GM power steering fluid that is available from any GM dealer. The GM part number for a quart of power steering fluid is 89020661. This fluid was especially formulated to operate with the Saginaw power steering pump. Also this fluid has been tested to be compatible with all the seals and hoses used in the GM power steering system. The previous GM part number for power steering fluid was 1050017. Both fluids work equally well.
  1. Lubricate the seals thoroughly with new power steering fluid before pressing them into the housing bore. Install the single lip seal first, then the back-up washer. (Make sure you install the seals with the spring pointing into the gear housing.) Drive the seal in far enough to provide clearance for the outer seal, back-up washer, and snap ring. Make sure that the inner seal does not bottom on the housing counterbore. Install the outer double lip seal and the second back-up washer in only far enough to provide clearance for the retaining ring. Install the retaining ring.
  1. The shop manual shows a tube that is used to press the seals into the housing. You want to press evenly on the seals. (You do not want to tear the rubber covering on the O.D. of the seals and you want the seals to be square to the housing bore.)
  1. Fill the pump reservoir with new GM power steering fluid to the COLD mark on the stick. Do not start the engine! Rotate your steering wheel to full lock right and left turns at least a dozen times. You should see large air bubbles in your pump reservoir.
  1. Refill the pump reservoir to the COLD mark. Now start your engine and allow the engine to idle for at least three minutes before turning the steering wheel. Turn the wheel to the left and check for leaks. Add additional power steering fluid as required.
  1. Remove the tape on the pitman shaft splines. It is now a good idea to smear waterproof grease on the pitman shaft and on the newly installed seal package.
  1. Reconnect the pitman arm, lockwasher, and nut. Torque the nut to 180 ft-lbs.

One last note: Early Saginaw power gears had two pitman shaft seals inside the gear. Later steering gears only had one pitman shaft seal. Either seal package will fit in any Saginaw pitman shaft gear housing bore.

RBGPitmanSealsReplaceRev10SE2007.doc