PLACE AN ORDER
What Everyone Should Know About Their New or Rebuilt
Ford Non-Integral Steering Boxes
This section is based on the Saginaw-style, Non-Integral Steering Boxes used on Fords from about 1960 to 1980. The term "non-integral" refers to the design of the box in that no hydraulic lines go into it and that the box itself offers no power assist.These boxes were used on most car model lines, both manual and power assisted steering. They were most commonly used on early Mustangs, Falcons, Fairlanes, Galaxies and Mavericks. While the information is intended for owners of new reproduction or rebuilt units, much still applies to used boxes.
Although the early Ford steering box, most notably the ones used in all 1965-1970 Mustangs, has a bad reputation for being loose and allowing the car to wander about the road, the box is actually a very good and sound design. Original Ford boxes, if adjusted and lubricated properly, kept from absorbing water, and not physically abused, is easily capable of lasting 150,000+ miles, being rebuilt and good for another 100,000. Unfortunately, some steering boxes have been so used, misused and abused over the years that many are no longer servicable. There are certain common problems that are found in these units and cause most of the damage. A little knowledge about these parts can significantly improve and prolong the service life of your steering box.
WATER & MOISTURE
When a steering box comes in for rebuild, the most common damage found inside is corrosion from rust. That's right, rust. Just a few drops of water inside a steering box and it will cause damage. Once inside, it has no way to get out. It will tend to settle in the lowest area it can, usually the bottom bearing area of the input shaft. Regardless of how much or what kind of grease inside the box, the water will wash the lubricant off and settle against the unprotected metal. Water is a most amazing solvent. It washes mountains down to the sea and it will wash the heaviest grease right off the steering box parts. If enough water gets in, and it doesn't take much, the water will cling between the teeth of the rack block and the sector shaft. You would think it would settle to the bottom of the box where the shaft comes out, but it never gets that far. It stays on top where the gears are and does its work.
And what it does is pit the parts with holes, which tears up the ball bearings and sheds metal into the box. Once the pitting starts, the damage rapidly increases. Particles of rust and metal shed from pitted parts gets ground into the surfaces of the gears and teeth with all the force it takes to steer the car. Not only does this increase the tolerances of the parts and play in the steering, it also damages the pieces to the point that they cannot be used in a rebuild.
But how does water get into the steering box? Well, obviously, if the car sits out in a wrecking yard without a hood, a fair amount of water is going to get on the box and some will eventually get inside. And those junkyard cars with no windows or door or steering wheels? The water just runs down the steering shaft and right into the top of the steering box. Kind of like a funnel, if you think about it. But how about the box that doesn't sit outside in the rain? The most common way is probably from water spray when washing the engine compartment, especially a power washer or a car wash.
Take a good look at the input shaft where it goes into the steering box. If you have a long-shaft box, the kind that the steering wheel bolts to the end of the input shaft, the shaft goes into a snout that screws into the steering box housing. If you can shine a light down into that snout where the input shaft goes in, you might see little shiny balls arranged in a circle. That's the top input shaft bearing. That's right, the top bearing. There is no seal of any kind. Now, maybe there is enough grease that has squeezed through the bearing that you can't see it that easily, but it's there, and if grease can squeeze through the bearing, then water can too. Because of chassis flex and general inevitable parts mis-alignment, there is no seal on the top of the box to keep out water. The steering column tube is supposed to cover this area, but pressurized water can easily be blown past and around it. On a long-shaft style box, this is the only place where water can get in.
Now, if you have a short-shaft box, the type that has a coupler on the input shaft that connects it to the steering wheel shaft, then you have it a little better. The short shaft boxes have a rubber grommet where the shaft goes into the box. This is not a seal, it is basically a rubber grommet that helps to seal out moisture. Ford went to this because the steering column tube cannot go over the shaft with the coupler on it, so they sealed the shaft a little better. Unfortunately, that rubber grommet gets quite a workout from 30+ years of exhaust manifold heat, shrinks and hardens. And it doesn't seal as well as it once did, so you better believe that a car wash or pressure washer can blow water past the grommet and into the box.
The long-shaft box basically uses the open bearing as a "vent" so exhaust manifold heat doesn't cause pressure in the box which might cause grease to be forced out the bottom seal. The short-shaft box, however, is "sealed" at the shaft so it has a "vented" grease plug on top. Although the hole in this plug is quite small, it sits right on top of the box and can easily have water forced into it from a pressure washer.
Water may not be the ultimate evil for your steering box, but it is something you should be aware of. Whenever yo wash the engine compartment or store the car in the weather without a hood, always wrap the steering box and the area where the input shaft goes in. Try not to spray pressurizes water on the box if at all possible. Don't worry about road moisture from normal driving. The water won't get get to the openings and engine heat will quickly evaporate the water away.
There are a couple of clearances that should be checked when rebuilding a steering box, but there are just two actual adjustments; input shaft bearing preload and gear teeth center mesh load. Any new or rebuilt box should already have these adjustments done to them and should require no further adjustments for many, many miles. Changing these adjustments in any way will probably void your warranty, so it is best to leave them alone and hope that whoever assembled the box knew what they were doing and built it right.
When the cars were new, and the steering boxes had a new parts inside, Ford recommended that you bring the car back to the dealership after about 4000 miles and the mechanics would check and possibly re-adjust the steering box. That was because a new box with new parts, much like a new engine, would break-in after a few miles and loosen up. The new parts would shed a little metal and the bearings would take a set. It wasn't much, but Ford thought it was significant enough to recommend it. A new reproduction steering box would probably act the same, and might require an adjustment after several thousand miles, but a rebuilt would not be as critical in this matter since the gears and such have already taken a set and have already gone through "break-in wear". In this respect, a properly rebuilt steering box, using good used parts, will probably remain tighter than a new reproduction box which will "wear in" more.
What all this means is that if you have a new or rebuilt steering box, you shouldn't change the settings or adjust it in any way. If the box is excessively loose, then that is a warranty problem. And if the box is out of warranty, you still should only adjust the box at your own risk. To do it properly requires you to remove the box from the car, have specialty tools and know exactly the correct way and order to make the adjustments. The measurements are in such small increments and units that it is impossible to make them without dial-type, low numerical inch/pound torque wrench, a specialty tool not commonly sold that costs $140 or more. For pictures and more detailed information on how to properly adjust a steering box, go to this page.
I know, I know, you've seen an article or read on a website how you can just tighten down that adjustment screw on the top of the steering box and all the looseness goes away. Well, that is one of the adjustments, but it is done after the other adjustment is done and can only be done with the correct tools. It is very easy to over-tighten the adjustment screw and cause the gear mesh to be much greater than it should be. At the least it can cause the parts to wear much faster and the looseness will return. Problem is, because of the accelerated wear, the parts are now too worn to take another adjustment and are ruined. In the worst case, the gear teeth can bind and break, which can cause the steering box to lock up in the middle of a turn. Not good.
All I can say is, if you can't do it properly with the right tools and conditions - don't do it. It can affect the life and operation of your steering box - and you.
While the steering box and its components are hardened steel, they can be fragile to a certain extent. Some of it is common sense, but I still get in parts that look like they were removed with a hatchet and pipe wrench. There are a few things to keep in mind about a steering box so as not to cause any internal damage.
If you ever have to remove the pitman arm from the bottom shaft of the steering box, never use a "picklefork". These tools
are destructive. Wedging a picklefork between the pitman arm and the box housing puts tremendous force on the sector shaft,
pulling it down in the box. This can damage the adjustment shim on the adjustment screw and it forces the sector shaft teeth
down into the rack teeth with far more force than these parts were ever intended to have. It can gouge the teeth, causing
excessive play in the adjustment, and it could break a tooth off of the rack block. Use a proper puller to press the arm off
the shaft. This puts no stress on the internal parts of the box at all. Pictures and sources for inexpensive pullers can be found
on this page. The pitman arm is hard pressed onto the tapered splines of the sector shaft and can be very hard to get off, even
with a puller. Some people have had the cheap pullers break on them trying to get the arm off. They suggest the best way to
use a puller is to tighten the puller down real good and then whack the end of the puller screw with a hammer to help "pop"
the arm off the shaft. This is not the thing to do. Hitting the end of the puller is like hitting the end of the sector shaft. It drives
the shaft up into the steering box and can damage the sector adjustment shim and the top mounting plate.
The end of the input shaft that goes inside the steering box has a ball bearing on it to center the shaft and allow rotation without play. When installing a steering wheel on the end of the input shaft, always line up the splines and use the tightening of the steering wheel nut to press the wheel onto the shaft. Never hammer the steering wheel down onto the shaft. When removing the steering wheel, always use a steering wheel remover tool. Never hammer on the backside of the steering wheel to get it off of the shaft. Any hammering on the shaft drives the hardened ball bearings into the bearing surface of the input shaft and leaved little "dimples" in the metal. You couldn't always see them if you had the shaft out, but they are there. These dimples cause the bearings to turn roughly on the shaft and make the steering wheel feel "notchy". It will eventually damage the bearings and cause the bearing preload to change and create play in the box. Be careful not to drop the box on the input shaft. One good hit and the smooth rolling action of the input shaft bearings could be gone.
I had a steering box mounted in a bench vise as I was assembling it. I had just installed the input shaft and set the input shaft bearing preload to the correct factory settings. The shaft had been freshly machined and the bearings were new, so it was perfect. For some reason, the box slipped out of the vise and fell about three feet to the floor. The input shaft didn't hit directly on the end, but on the side as it fell. I mounted the box up again, making sure it was securely fixed this time, and re-checked my previous adjustment. The shaft turned rough and notchy as if there were detents in the bearing. That little fall was all it took. The shaft had to be re-machined again and the bearings replaced. You couldn't see the damage, but it was there. Use common sense. You can use a soft hammer to tap a coupler onto an input shaft, but never pound it on with force.
When you buy a new or rebuilt steering box, it should already be fully filled with grease and should not require any additional grease for many years. Any rebuilder worthy of the name should see that the box is fully and properly lubricated but, quite frankly, some are cheapskates and don't fill the box up. They put grease on parts as they put the box together, but they don't fill all the hollow space inside like they should. If you are unsure if your box is fully filled, go to this page to see how to properly fill your steering box.
Now, just because some rebuilders are stingy on the grease, doesn't mean that Ford always did such a good job themselves. I have seen quite a few steering boxes that I believe to be untouched that didn't have much grease from the factory. I have seen some that didn't have a thimble full all together. And I've seen some boxes with rear axle lube inside them, more on that later.
A steering box needs to be filled with grease to be lubricated properly. Grease tends to stick to parts, and when the sliding action of the gear teeth wipes the grease off of the teeth, it needs to be constantly re-applied. Now, the proper grease is designed so that the heat from the exhaust manifold keeps the box pretty warm and the grease soft enough that it will "flow" to a certain extent, but that also means the grease settles and puddles in the bottom of the case. Unfortunately, the gears and bearings are in the top of the case.
When you turn the car, the rack block moves up and down inside the box housing and the sector teeth move side-to-side. There is only so much room inside the case, so the parts don't have a lot of room around them. When the box is properly filled, the action of the rack block moving up and down in the box and the sector going side-to-side actually causes the box to "pump" grease from one end to the other. When the rack block moves up in the case, all the grease that's in that area has to go somewhere, so it is squeezed around the rack down to the other end. The opposite occurs when the car is turned to other way. This constant "pumping" of the grease is what keeps fresh grease being applied to all the parts. Without this pumping, the grease would wipe off the parts and stick to unimportant areas of the box and corners inside. But for this pumping to work, the box must have enough grease inside that the parts move it around.
So it's important that the box is full as it can be with grease. You can't really "over fill" a box with grease. Because the boxes are vented, so to speak, any excess grease just gets pushed out the vents until an equalibrium is reached. That is why sometimes you see grease coming out around the input shaft or fill plug on new or rebuilt boxes. It is just the excess being forced out because the box is a little too full. As soon as it is all equaled out, the seepage will stop.
There are some websites on steering box rebuilding that state the box should not be over-filled, and that doing so can cause a problem. This is nonsense. Although they are describing a Saginaw reciprocating ball steering box, they are talking about one from a General Motors car, specifically a Camaro. For some reason, they did not include a vent on this box, nor is there any feature of the box that allows venting, so over-filling this box could cause a seal to blow out or leak. The Ford design box does not have this flaw and will simply vent excess grease without problem.
It is also important to use the proper grease inside the steering box. Notice I said grease, not oil. Some people pour 90-weight gear oil in the box thinking that it is an axle or transmission or something. Oil puddles in the bottom of the housing - the important parts are in the top of the housing. The seal on the bottom of the box was designed to contain grease, not oil. Now, you can check your owners manual or shop manual for the exact specification of the grease that Ford recommended for use in the steering box, but I have found that any good modern lithium or moly-based chassis grease will work well. It is designed for high load lubrication, softens sufficiently from engine heat and clings to parts. Never use wheel bearing grease. It is designed for high heat and does not soften as it should. Plus it is not designed for gear compression operation. And please don't put any liquid oil into the box. It doesn't work effectively and I hate it when during a rebuild I remove the sector shaft from the housing and the box poops all over my floor.
Although the grease in the box should last the "life" of the box, keep in mind that if you have headers on the engine, the box will get much hotter and the grease can cook inside the box. I would consider trying to pump as much fresh grease in the box, and in doing so, force out as much of the old grease. I would try to do this every 50,000 miles if there are headers on the car. I see a lot of boxes come in that the fluid is burned so bad it has started to cake and harden. This also probably applies to cars like big-block Mustangs where the engine is wider and sits closer to the steering box.
So for a happy and long-lived steering box, make sure the box is completely full of a quality lithium or moly-based chassis grease.
The steering box has a certain amount of travel in it. The input shaft has a worm-style gear on the end and the rack block moves up and down the worm as the wheels are turned. The rack will only move so far before it bottoms out on the case housing. When mounted in the car and all hooked up to the linkage and suspension, the steering stops located on the lower arms stop the linkage before the rack bottoms out inside the steering box. If you turn the box without having it hooked up to the linkage, it is possible to bottom the rack in the box. Now this is not normally hurtful, but if you turn the steering wheel real hard in this situation, it is possible to damage the inside. The steering wheel gives you tremendous leverage on the steering box and you can easily over-stress some of the parts this way. Even with everything hooked up as it should be, once you hit the turn stop and the steering wheel will not turn any more, do not hard force it to turn more. The recirculating ball bearings around the worm and rack travel through tube-like guides that can literally rupture under such high pressure. Sometimes the bearing balls themselves will break. They are very hard steel, and when they fracture, they split right down the middle into two equal pieces. The problems is, these pieces are not round and they jamb up against the other bearings and the box locks up. Remember, when the steering wheel stops turning because the linkage has moved as far as it will go, trying to turn the steering wheel like the proverbial 500-pound gorilla can cause damage inside the box.
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