A Pitman shaft is a column extending from the steering sector, which attaches to the Pitman arm, which moves the tie rods. Depending on the turn direction, the fluid from a pump moves a piston forward or backward. This action moves a nut, which turns the Pitman shaft and steering linkage. The movement inside the steering box causes the Pitman shaft and arm to rotate, applying leverage to the relay rod, which passes the movement to the tie rods.

Disconnect the steering shaft from the steering box input shaft. Often the upper end of the steering shaft will have a splined section, which will allow the shaft to be collapsed slightly and enable you to clear the steering box input shaft. Next, look for the large bolts attaching the steering box to the frame. Remove this hardware, being careful to support the surprising weight of the steering box as the last bolt is removed. Lower the unit down and out of the underside of the vehicle. If this is not possible due to space constraints, the box will have to come up through the engine compartment, which may require temporary removal of accessories like the alternator or power steering pump. On vehicles equipped as such, check the ball joint on the end of the pitman arm for excessive play, and if you have not already done so swap the pitman arm to the new steering box. Install the new steering box in the vehicle, reattach the steering shaft, hoses, and steering linkages, being sure to torque all hardware to the manufacturer's specifications. Refill the power steering pump reservoir with the proper fluid, reconnect the battery, and start the engine. Look for any fluid leakage, then begin turning the steering wheel back and forth from lock to lock. Shut off the engine after each pass, checking and refilling the power steering pump reservoir to the proper level. Air will slowly escape the system, so check the fluid level every few days after the installation. Assuming the ball joints and the rest of your steering components are in satisfactory condition, you should now be enjoying "like new" steering, and vehicle wandering will be a thing of the past!