Vega Boxes that Last a Lifetime...Who Said it Couldn't Be Done?

by Dick Zakrzewski

When I tried to rebuild my Vega steering box I found I could no longer buy a replacement pitman shaft and ball nut from GM and could not buy them from vendors selling reproduction Vega boxes. So I set out to grab another box from my local bone yard. I soon found another box like the one I had. I went out again and found even more boxes. After opening all the boxes found on this last trip, I finally found a good pitman shaft and nut. But, I noticed that all these gearboxes had one thing in common. They were all packed with grease that had dried out. This lack of lubrication had ultimately resulted in premature wear to each box's vital parts. At first I thought someone had used grease in the gearbox because its seals had gone bad and was leaking oil…it's an old trick. But then I learned GM had packed them with grease from the factory! I'm quite sure they never saw fresh grease again.

After cleaning all the parts including used ball bearings salvaged from I don't know which gearbox, I coated the parts with 90W-gear oil and assembled them in the gearbox. To assure a long life for MY Vega box I then filled the box with 90W-gear oil. I like the gear oil because it doesn't dry out and keeps the balls in the ball nut circulating freely.

It didn't take long for me to see why GM used grease. The next morning I noticed a puddle of gear oil under my steering box the size of a dollar bill. The oil was leaking past the threads of the worm bearing adjuster at the forward/lower end of the gearbox. See Figures #1 and #2 for correct nomenclature.

Figure #1

Figure #2

Undaunted by this turn of events, I decided I would try an inexpensive fix. I proceeded to remove all the oil from the gearbox. You can take the box off the frame and dump it out or you can do like I did and wait a few days until it all leaked out. I removed the lock nut and thoroughly cleaned the exposed threads of the worm bearing adjuster (see Photo #1) and the lock nut with some grease and wax remover then applied a shot or two of contact cleaner. You want these surfaces really clean. I then coat two or three threads of the worm bearing adjuster nearest the gearbox with high temperature silicone sealer (see Photo #2). Wait a couple minutes before replacing the lock nut (see Photo #3).

Photo #1

Photo #2

Photo #3

Note: I selected the high temperature silicone after placing a small amount of a couple different silicone sealers on a plastic strip and found the high temperature sealer set up the quickest. You want the silicone to set up as quickly as possible in the event a small amount of residual oil tries to leak out while the silicone is setting up.

Now you'll want to vent the gearbox. Remove the side cover bolt nearest the frame rail (see Photo #4). Drill a small vent hole into the side of the hex head and another down the center, just down to the one you drilled in the head (see Sketch #1). If you mark which face of the hex head faces back before you remove it then drill from that face, your vent hole will face backward when finally installed. You need to vent the gearbox because installing an unvented screw could act like a piston and create hydraulic pressure that could damage the seal you just created.

Sketch #1

To make sure the seal you just created has set, I suggest you wait 24 hours before filling the gearbox with 90W oil. You can easily fill the gearbox by inserting a straight section of coat hanger in the "through" tapped hole in the gearbox. It is one of three used to secure the side cover (which is located on top of the gearbox). Don't know why they call it a side cover! Allow oil to flow down the wire into the hole (see Photo #4). This way you don't have to be directly over the hole to fill the gearbox.

Photo #4

Install your vented bolt and your ready to go. The gearbox will now last the life of the car without creating a mess on the garage floor.

Dick Z