Steering Box Rebuild - Steering You Straight

Position the new race for the worm-bearing adjuster and seat it with the properly sized driver.

With the race installed, wheel-bearing grease is forced into the bearing. The grease will also keep the bearing in place when it's time for assembly. The case will not be filled with grease, however-it's too thick. More on this later.

Place the ball nut on the wormshaft. Be aware that the teeth of the ball nut are tapered, as are the teeth on the Pitman shaft. Therefore, the ball nut must be properly orientated or the Pitman shaft will not seat fully. As the ball nut sits in the housing, the valley between the teeth gets progressively narrower looking down into the housing. With the ball nut properly oriented, feed the balls into the openings. It will be easier if you lift the end of the shaft slightly, so that the balls can travel all the way down the threads, eventually resting on the I.D. of the ball nut. Sound confusing? It will become apparent when you're loading them in. Now reposition the guides before placing the last few balls in each thread. Even with all 25 balls in each thread, there will be space left over for two or three more balls. This is normal so don't think you've lost some. Secure the guides with the retainer and screws.

The balls have been loaded and the ball guides are in place. If you look closely, you can even see two of the 50 balls that make up the threads. Next, set the ball-guide clamp in place and secure it with the three screws.

Once all the balls are installed and the retainers are in place, coat the wormshaft and ball nut with heavy weight gear lube. We used 85W-140-its viscosity is low enough to find every nook and cranny, which is vital for durability. You want to be sure every surface is covered. For now, set this assembly aside.

Back on the case, tap in and seat the upper worm-bearing race using the properly sized driver.

Because the rebuild kit serves a variety of boxes, it is necessary to cut the supplied Pitman shaft bushing to size. Simply measure the depth of the bushing you removed, apply it to the new bushing, and carefully saw away. You could also use a rotary cutting tool if you prefer. Dress the cut with emery cloth to deburr the end of the bushing prior to installation.

Without a doubt, driving the bushing into place is the trickiest part of the rebuild. Use wood blocks to keep the housing level and steady. Place the bushing squarely in the opening; using the correctly sized driver, gently tap it in, checking after each blow to make sure that it is going in straight. Once it's squarely seated, reinsert the Pitman shaft and turn it just to ensure it has free rotation on the bushing; then remove the shaft again. If there is a slight bind, you can use Emory cloth to dress any high spots.

With the bushing installed, you can now drive the Pitman shaft seal into place. Repeat this same procedure with the wormshaft seal.

Having previously soaked the ball nut and wormshaft in gear lube, add some grease to the shaft and teeth. When it comes time to fill the assembled and installed box, Sam at Harry's Steering Gear Repair recommends a gear lube/grease blend. You want a thick liquid, not a thin paste. It should be pourable. This viscosity will handle the load yet not be so thick that it becomes stiff and flakes off the moving parts; nor will it be so thin that it seeps past the rubber seals. Place the well-greased upper bearing on the wormshaft and ball-nut assembly and insert them back into the housing.

Making sure the ball nut is centered, tighten the worm-bearing adjuster until there is no perceptible endplay. Next, place an 11/16-inch, 12-point socket on the end of the wormshaft. It will fit the splines of the shaft perfectly. Using a torque wrench calibrated for inch-pounds, turn the wormshaft back and forth as you tighten the worm adjuster. When the wrench registers between 5 to 8 in-lb, it's tight enough.

Next, tighten the locking nut (using a hammer and a wood block to avoid damage to the retainer); then center the ball nut in relation to the opening in the side of the housing. You can eyeball it.