VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Adjusting Steering Box 1939 Master Deluxe

The pitman arm on my ,39 Master Deluxe coupe has a two piece pitman arm. The two pieces are held together by two bolts. The one end is connected to the pitman shaft and the other end of the pitman arm has two ball & socket connections ....one to the right side steering linkage and the other to the left side. The '39 shop manual on page 220 shows illustrations and instructions for steering box adjustments. For the Master Deluxe it reads "it is necessary to remove the pitman arm before making adjustments" and for the master 85 it reads "disconnect the steering connecting rod from the pitman arm." I read this as that for the Master Deluxe the arm should be "pulled" but on the Master 85 the pitman arm remains on the shaft and disconnected from the steering linkage tie rods. On my Master Deluxe do I actually need to Pull the pitman arm off the shaft or can I just disconnect the end pitman arm from the steering linkage and keep it attached to the shaft? I would think that it could be left on the shaft to make adjustments. It seems that it might be easier to keep the arm on the shaft and also the Pitman arm can be manually moved to check while turning the adjusting screw. Is there a specific reason that the arm must be Pulled from the shaft?

If I choose to disconnect arm from steering linkage keeping the arm on the shaft can I just separate the two pieces of the arm and make adjusgments or is it best to keep the two piece pitman arm intact and disconnect it from the tie rods? Long story for a short answer. Thanks for your help.

Your thinking is correct. Before you make any steering gear adjustments you need to remove any load that turns the wheels.

Whether you pull the pitman arm off the box or separate it or disconnect the steering links from it will give the same results. It is really a matter of which method to disconnect the steering linkage is easiest for you.

Follow the process in the shop manual including the first step to check how the steering gear is sitting on the frame. Also remember to back off all 3 adjustments on the box before you start the proper sequence of adjustment. Each adjustment sets the baseline for the next one.

Steering Column Alignment

First make sure the hard rubber bushings beteen both halves of the pitman arm are in good condition. If they are shot it wi produce a lot of steering play.Often grease soaked from oii lleaking ffrom steering gear.
The gear adjustments can be made with the arm in place, You can go by feel'
More common for tthe steering gear to be worn out due to driving for years with no lubrication.

Regarding Steering Box Adjustments on 1939 Master Deluxe. The service manual lists 3 adjustments to be done in specific order. The worm shaft end play should be removed first; next, the roller shaft end play; and last, the back lash between the worm and roller sector. Another older Chevy manual I referenced stated that "Worm shaft end play is evidenced by up and down movement of the steering wheel". I have no up or down movement of the steering wheel when I try to pull it up & down. Does that mean that there is no dsworm shaft end play? If so, can I skip this adjustment and go t0 steps #2 &#3?

Thank you Rusty & Gene for your response to my original post - 10/19/21. Maybe I'll finally get this adjustment done! Thanks VCCA members for all your help.

Gary Lovell - Marion, Ohio glovell39

That adjustment is seldom necessary except after complete overhaul.

Anoher location in the steering that can cause play in the 1939-1948 models is the pitman arm. it is in two pieces with hard ruber gromets between. Common for the gromets to decompose from the lube leaking out of the steerng gear.

My preferred process is to back all the adjustments off so there is looseness in all 3 areas. With this approach I know that I am setting the correct pre-load for each type of motion.

The “up & down” is really what I call “in & out” when you pull and push the steering wheel parallel to the direction of the steering column.

Gene’s post reminds me that there is one other area to check. Make sure the bearing at the upper end of the steering is not worn. This would show up as “side to side” motion of the steering wheel.

Rusty & Gene, Thanks again.... Your help is appreciated. Wish me luck.

Thanks again. I did with your advice and the service manual instructions adjusted the steering box on my '39 Chevrolet. While I had the front off the ground I also put on new tie rod end rubber seals and greased the tie rods and front suspension fittings. WOW! The steering wheel .play is significantly less. I could not have done this without the help of my fellow VCCA members. Thanks to all my Chevrolet friends.
My next venture is to get my odometer unstuck.
Gary Lovell #351178 Marion, Ohio

That is great! Thanks for letting us know the results.

Would the instructions from a service manual for a 1938 or a 1941 fit more closely to a 1940 Master Deluxe? I have a huge amount of play in my steering and can't determine whether either of these service manuals online would be accurate. Thanks in advance for replies!

The 1939 to 1948 steering gears and general steerig parts are the same EXCEPT 1939 AND 1940 WITH FRONT LEAF SPRINGS.

Thank you for the quick information! It is very helpful!

Get under the car and have your assistant turn the steering wheel back and forth. You may find the play is coming from some oil soaked bushing or other out of adjustment connections.

My 39 steering gear pitman arm bushings were shot and replacement took almost all the play out of the steering. Steele rubber has them for about 12 bucks each.

Dave