The Stovebolt Site Forums The Shop Area Driveline 3 speed 4 speed stering box

Can someone tell me the difference between a (1947-53) Steering Box-Rebuilt-3spd and a (1947-53) Steering Box-Rebuilt-4spd? My truck is a "49" 3100 with 4 on the floor. I've called all around the States, most folks have told me to mail my old one to them and they will send it out and might take up to 6 months to get it back. I believe they send to Lares Corp. I called Lares. It will cost $500 + Shipping back. The turn around time is 8-10 weeks. Classic Parts have the 3 speed in stock. The adjustment screw in my "49" is in as far as it will go.

The three speed transmission is a column shift (three on the tree), so there are extra holes on the column to mount the shifter.

You should be able to swap your original column from the 4 bolt connection on the top of the box up to the steering wheel on to a replacement 3-speed steering box. That will deal with the extra holes that bartamos mentioned. Pretty easy to do. The column holds the upper worm bearing race, so you should reset the turning resistance with the big adjustment plug on the end of the steering box. You could probably just measure the steering wheel turning torque before removing the 3-speed column and set it to the same number after installing the 4-speed column.

Which adjustment screw? Lash or worm?

Worm. Your picture shows a 4-bolt connection on the lower end, but my steering box '51 3100 3 on the tree, has those 4 bolts on the upper end, disconnecting the column.
Your pic is the steering gear for the 3/4 and 1 ton Forward Control, 1-1/2 ton school bus and all 2-ton trucks, per the service manual exploded diagrams.

Oh sadness! Surgery required.

I got my picture from http://chevy.oldcarmanualproject.com/booklets/52mts20/index.htm to show the adjusters for a quick reference.