1989 Chevy truck steering shaft moves in and out of firewall

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Q&A: 1989 Chevy Silverado Power Steering Pump Removal

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Feb 17, 2008 - you need to remove the belt getter a power steering pump pulley pulling kit and remove the pulley unbolt the lines unbolt the pump reverse ...

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Open the hood and have someone turn the steering wheel. Look to see if the steering shaft is moving at the firewall, If not, then the steering wheel shaft in the column is bad. If it moves, then the connection to the steering box could be bad. Look to see if the steering box pitman arm, the part that comes out of the lower part of the steering box moves. You may have broken steering linkage.

I would pull the plastic trim panels and see if you can find where it isn't connected to the lower portion of the shaft.

Not sure what type of Chevrolet you have, but a lot of pickups in that year had trouble with the intermediate shaft (Between the column, and the steering gear) It is a type of 'slip joint' that allows movement between the cab, and the frame, it has a nylon insert that wears out over time. The new one has a larger shaft, looks longer lasting. Pretty easy to replace too. - Seems a few full size Chevy vehicles used this shaft. You can actually feel it if you have someone move the steering back and fourth while you put your hand on the shaft.

you need first disconnect negative battery cable. you need steering wheel puller you have to remove steering.look under hood disconnect flange end of the steering shaft at the flexible coupling separate the coupling from the lower end of the steering column. you have to go inside vechicle remove lower steering column cover yoo have to remove steering column dash to panel screws then you have to remove shift linkages and remove disconnect electrical wiring connector to turn signal and ignition switch.your model truck shouldnt have the floor board mounting screw hold column to the floor.

The "knucle" you are describing (The part with the U-joint built into it) is called the Intermediate Shaft.
It is somewhat common for the U-joints in this shaft to get loose. It is not difficult to replace. You just remove the bolt from the steering column main shaft under the dash and remove the bolt from the steering gear assembly. The shaft will then "collapse" or "push inside of itself" to provide the clearance to remove it from both ends. The hardest part is working the rubber boot out of the way where it goes through the toe-board. The boot is actually 2 pieces and can be moved in and out of itself as well, but can be somewhat difficult to get it moved out of the way far enough to work wjth the bolts at either end.

CAUTION: When removing the intermediate shaft, extreme care must be used to make sure that the upper steering column shaft (and steering wheel) does not rotate. If this rotates around, the contact assembly for the airbag can be damaged. When I am doing these, I usually take a bungee cord and run it from the steering wheel to the brake pedal lever. This will allow a little movement to work with the shaft while at the same time, preventing the steering wheel from rotating all the way around.

You will have to tear down the steering wheel ,column,and tighten the large philups screws.

Check your steering kuckle located above gear box on shaft that goes to steering wheel, while some one turn's wheel a little back & forth and check for slack, Also check front end linkage for looseness, don't forget wheel bearings.

heve you checked your steering fluid? if the fluid is of check the bearing of steering pump and also the bearing of the tensioner.