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Truck kingpins


WPVT
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The steering on my 1928 1 1/2 ton White is stiffer than it should be, making it hard to drive anywhere involving a turn.

On jack stands, the steering, and the kingpins are pretty free of binding. The steering box is properly adjusted and is smooth from end to end. 

I am wondering if the king pin thrust bearings could be bad enough to make steering hard once there is weight on the wheels. The kingpins have been greased and they took the grease. 

I don't know much about those thrust bearings, i.e., what kind of bearing they are. I doubt they age well. My question is that if they are dried up, would that be enough to make the steering stiff ? 

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I wouldn't think so, if they were bad enough to affect steer then you'd have up/down freeplay.  Its winter, I'd take it all apart for a looksee.  You describe it as all being in good condition so I'd wonder if you were trying to steer it static, it should be moving before trying to steer it, you'll put excessive strain on the steering box unless its moving, that and tire pressure has to be up to snuff.

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Thanks. I'm aware of the things you've mentioned. 

 

What I am experiencing is not a result of low tire pressure, ungreased linkage, lack of lubrication in the steering box, or steering while the truck is stationary, although I appreciate your suggestions. 

I'll figure out a way to evaluate the thrust bearings in place, as it doesn't sound like anyone has had direct experience with the bearings as a separate issue from the kingpins. 

 

There are many components to the steering system that could contribute to the stiffness. I've checked them all out before posting my question about the thrust bearings.  

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Well, I might as well belabor the obvious too..

You didn't mention if the stiffness had been gradually worsening or had  more suddenly occurred...

 "Stiffer than it should be"... how/who/what determined how stiff it should be??  If personal experience with this or other period similar trucks, a valid statement..unless, of  course, it's a White idiosyncracy of your model...

On this point, I assume you belong to one or more of the White Truck groups; have other owners of your model, or other 28s, agreed there was a problem somewhere and/or offered suggestions you didn't exp;lore?? (You do seem to've covered every likelihood except your original question above)...

Last, but most regretab;y presumptuous, how long have you had the truck?? You're not remembering how easy it was to steer 20 years ago??

The old complaint "This thing steers like a truck!!"  did have a basis...

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Thanks. I don't drive the truck very much and the steering is the same as it was after I bought it. I've been gradually working through all of the issues that it had.  I've got pretty good upper arm strength and I think I can say with certainty that it doesn't work the way it should. I've owned plenty of non-power steering trucks over the years, including some with nearly frozen kingpins. I once drove cross country in a GMC that wouldn't make a 90 degree turn. Tricky in urban areas.

 The White truck groups are focused on later models mostly, the over-the-road tractors. Mine is a Model 60, 1 1/2 ton that was popular for in town delivery purposes. I'll get it working properly once I figure out the problem, I was just curious about the thrust bearings because without load on the kingpins, everything moves pretty easily. 

Thanks for "belaboring the obvious." That's always a good starting point. 

 

Looks like I'm going to have to get dirty...

 

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I am fortunate in that I have detailed parts manuals for this truck with excellent diagrams. That may help me to understand how the kingpin assembly is supposed to work, and how it might be malfunctioning. 

First off, there is no thrust bearing, just a thrust washer. The kingpin appears to be mounted in the axle with a taper, which seems like a good design when it's time for replacement. It is the bushed top and bottom, the upper bushing being smaller than the lower, since in between the two it is tapered.

So here's my guess....the kingpin may be seized in the steering knuckle bushings where it is supposed to be rotating. If it is instead rotating in the axle (where it is supposed to be staionary), that's where the kingpin is tapered. It stands to reason that this (if it's loose) would rotate fine until you put weight on it, at which point it would be pretty stiff. 

With the axle on jackstands, if someone loosened the upper nut on the kingpin, gave it a rap, and then forced grease into it, they might think they were freeing up the pin.In fact, they would be loosening the pin from the axle, where it is supposed to be fixed, and leaving the top and bottom bushings frozen.

So I think I've figured out the problem without getting dirty !

I'm hoping that I can get the kingpins out (should be easy since they are tapered), clean up or replace the bushings, and put it back together with the kingpins rotating in the bushings, not in the axle.  Fingers crossed that I won't need new kingpins. 

Even if the taper is worn a little they should still seat firmly if I make the necessary adjustments. 

 

Here's a question...Assuming that fixing the kingpin in the axle is the usual method, is doing it with a taper common ?

 

PS Just researched and answered my own question. The tapered mount is how Mack truck kingpins work. Tightening my top kingpin nut should pull the pin up into the axle and seat it firmly, so that the pin will then turn in the bushings, not in the axle. I'll try that tomorrow.

 

Edited by WPVT (see edit history)
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Update: I was wrong about the tapered kingpin rotating within the axle. The kingpin is operating just as it should. So my focus has turned back to the thrust bearings that take the load of the truck's weight on the front axle. On this truck, the thrust bearings are in fact, just thrust washers. They came from the factory with zero vertical play, so there really isn't much opportunity for them to be lubricated. I backed off the castlenut one notch to give a bit of vertical clearance and put 90W gear oil in with the grease in hopes that it might get to where it would do some good. I cranked the steering back and forth a number of times with the axle jacked up, and again with the wheels just touching the floor, so that the vertical clearance would open up and close. We'll see if this makes a difference.

It seems remarkable to me that the thrust of 1/4 of the weight of the truck would be placed on a 2 " washer, but that's how it works.  

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I’m curious, when you adjusted your steering box were the wheels in the straight ahead position? If not it will behave as you describe. With the front end of the ground , you should be able to move the tyres lock to lock by hand. It should be tough to get it to move when wheels are centred , but once you get them moving it should swing lock to lock. 

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I'll give that a try...as I recall I couldn't quite move the wheels by hand. 

I'll also revisit the steering box adjustment. 

My primitive understanding is that if the wheel returns to straight on its own after making a corner, that it isn't adjusted overly tight.  That understanding came from experience trying to adjust out the play in older steering boxes. Maybe there's more to it than that.

 

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The solution to this problem continues to elude me. 

When the front axle is jacked up, the kingpins and associated steering linkage have near zero friction. Likewise the steering column, and likewise the steering gear box itself.

The steering wheel moves the front wheels through their range of motion quite easily. It is definitely not possible to turn the front wheels and make the steering wheel spin, however. It feels like the gear ratio within the steering gearbox wouldn't enable that. I've never given much thought to the ratio of a steering gearbox, but it must be designed either to be easy, or to be quick. 

In any event, once the front wheels are on the ground ( stationary or in motion), it requires an unreasonable effort to make a turn. (I've had plenty of trucks without power steering, so it's not a matter of perception.)

It may be worthwhile to jack up the front end and try the steering with someone offering resistance at the tire. That will give me a sense of how much leverage I actually have at the steering wheel.     

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Try putting a couple of cookie pans loaded with liquid dish soap under the tires. Then try to turn the steering wheel. If it turns relatively freely the issue is the tire, if not then the steering assembly.  I am betting on the tires gripping the road very well. We have a 46 Chevrolet flatbed on our ranch. That truck is almost impossible to turn if there is no forward or reverse motion to the truck.  Let us know as we are all curious to hear the findings.

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Thanks. That's good advice. I'll give it a try. Maybe a set of those wheel dollies would be just the thing.

I expect difficulty when the truck is stationary, but this problem is evident when moving as well. I think it is interesting that it steers very hard, yet straightens itself out nicely after the turn. 

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Perhaps you can locate/borrow a set of those old Hunter Wheel Alignment plates to set the front end on, they'll turn and you'll be able to quantify the resistance.

Is it equally difficult turning to left or the right?  Like if it had too much caster?

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Interesting problem. White vehicles were very well built. I would expect they purchased a steering box from an outside supplier by the late 20's. A 1 1/2 ton truck is just about the same as a Cadillac or Packard car. I have seen crazy things bind steering systems.......a rope seal on the chrome cosmetic steering column........actually making the car steer very poorly. I would disconnect the drag link and center link between the two spindles, get it so you can individually turn each spindle by hand. Usually by the time you are this deep into the steering, it's easier to just pull everything apart. Installing king pins can be a huge task.......making the parts, and pressing them in and out....as well as installing new bushings in the axel........Some spindles have bushings, others bearings. It's probably got old rock hard grease in a joint somewhere. The advantage of doing everything is when you're done, you can align it properly for todays roads and driving habits. It was probably set up for dirt roads with a full load at lower speeds. Post a photo of the steering box, and front end parts.......especially the spindles. Thanks, and good luck. 

Edited by edinmass (see edit history)
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Thanks Ed. The White is a very well designed truck. They even mention their steering gear box in the maintenance manual, their improvement on the usual segment and worm. They use a half nut for more surface contact.

When jacked up, the kingpins and linkage are all very smooth with no friction. I addressed small problems within the steering column, and that no longer has any appreciable friction.

The gearbox seems to be operating smoothly,and I have adjusted the worm end play to provide some clearance, but not bind. There is another adjustment screw for end play in the gearbox steering shaft (the shaft at 90 degrees to the worm).  I'm curious about that, since it doesn't seem to affect the end play in that shaft. Maybe something is amiss inside. 

I think I'll try putting the front wheels on dollies or something, so I can load the kingpins, but not have the tires surface friction as part of the equation. 

 

A gentleman posted from NZ suggesting that with the axle jacked up, it should be possible to rotate the steering wheel by angling the tires back and forth. Looking at a cutaway view of the gearbox, that seems unlikely. The worm thread would have to be cut at a very steep angle for that to be possible. If I measured the number of turns on the steering wheel that it took to move the steering gearbox lever a given distance, I could compute the mechanical advantage. Trying to move the steering wheel with force on the tire would be a mechanical "disadvantage".  Or am I mistaken ?

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Not sure about the box moving when you move the wheels. Depends on design, and a truck is usually a high ratio box that generally wouldn’t allow it. I have done a bunch of boxes.......and a lot of early cars, trust me on this, pull the center and drag link and then check the spindles. Ball and cup binding, rusty tie rods, bad box, binding wheel issues to the column.....there are lots of strange places to have an issue, many you wouldn’t think would cause a problem. The end play adjustment on the box is for the sector shaft and almost never needs adjustment. By disconnecting everything you can get a feel for it all. Leaving everything hooked up is a waste of time. I would expect your truck to steer well. My 1917 White steers like a 1932 Ross box. Photos would help a lot. If you go through everything, it will be easy to align. What size tires are you running, as tires often cause steering issues. Again, lots of photos will make it easier to figure out. There are no shortcuts in steering systems......or any other as a matter of fact. Photo is the boss with my car......over the weekend.

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Edited by edinmass (see edit history)
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Also, expectations can be off.......all cars and trucks are very hard to turn when still, and as soon as you have some forward movement, it should steer easily. 

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1 hour ago, 37_Roadmaster_C said:

You are correct about mechanical disadvantage, however with the wheels off the ground, I have not found a vehicle yet that you can not move the spindles (wheels) lock to lock by hand. Sometimes it takes an effort to get them moving, but they will move.


On a worm and sector or lever I agree you can move the box from the wheels with it jacked up. I’m not sure you can do it on an acme thread and nut..........my guess is it would depend on the ratio. 

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That's interesting. With the truck wheels off the ground, I cannot move the wheels through their range of motion. This is, however, a pretty heavy truck, and I would imagine they would have used a fairly high steering ratio compared to a car or pickup.

Later this week I'll compute the steering ratio on this truck. 

Does anyone have an idea what a typical steering ratio would have been on a 1920's era medium weight (not a pickup) truck ? 

 

PS The steering difficulty is evident while making turns in motion, not just while stationary. As I mentioned before, the steering does return straight after a turn without having to crank it back. This one thing would seem to indicate that maybe the steering is operating properly. 

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8 minutes ago, edinmass said:


On a worm and sector or lever I agree you can move the box from the wheels with it jacked up. I’m not sure you can do it on an acme thread and nut..........my guess is it would depend on the ratio. 

The worm and half nut is similar to the worm and sector, just more contact between the threads.  I have a diagram of the box that I'll post later in the week.

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Wheel return is from positive castor in the front end......on a truck, it’s probably 4-5 degrees positive.......the wheel will return with that kind of angle. Today, with better roads, faster speeds, and modern tires, I would align it to 0.5 degrees positive and 1/8 inch of toe in. Camber is not adjustable unless you bend the front axel. Jack it up, and pop off the center and drag links, and then try and feel binding in the spindles. You can take two 12 inch square pieces of heavy plastic or Teflon sheet and grease them and use them as turn plates. With the center and drag link off, you should be easily be able to turn each wheel with the front end load on it. I have a set of old Hunter turn plates I bought at a swap meet for 50 bucks. Cleaned them up and they are perfect for pre war cars. Photo is a Model J with a modern alignment guage on it.....works great, my total investment is under four hundred bucks, and I can do my own alignments in the shop. I have compared my set up with a car on a modern machine......they were the same.

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By the way.......both of us are driving early trucks......mine just has more seats! 
 

Actually, my car is very lite and handles like a much newer car.......a tribute to the engineers at White Motor Company. What’s the comfort zone speed on your truck? 35 MPH?

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Just now, edinmass said:

By the way.......both of us are driving early trucks......mine just has more seats! 
 

Actually, my car is very lite and handles like a much newer car.......a tribute to the engineers at White Motor Company. What’s the comfort zone speed on your truck? 35 MPH?

I haven't found the comfort zone in my truck...yet. It was designed to be a "high speed delivery", so 35-40 mph isn't bad. Though nothing is malfunctioning, things do get a little loud. It only has 12K miles on it, so it's pretty tight. 

 

I hear you loud and clear about disconnecting the linkage. I'm working my way up to it. 

You are right about the caster. My point being that the steering, stiff as I might find it, doesn't prevent the wheels from straightening out while in motion. I've had vehicles with stiff kingpins or stiff gearboxes that you had to crank back out of the turn to avoid going in a circle. A lot of work to drive that way.   

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Funny, my car only has 11,200 miles on it. Seems people like to save low mileage White Motor Vehicles. There are a bunch of White truck fans who are active in the hobby, all a nice bunch of guys.

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My brother in law and I did the Gemmer steering box project..........probably the most difficult box on the planet to deal with. We had about 1200 hours in design, engineering, heat treating, research, and background in them. We were the first to be  successful in doing a total rebuild. We used modern seals, replaced bushings with bearings on the sector shaft, and made a modern Teflon seal to keep the box from leaking. We used purpose manufactured bearings for steering boxes.....which are high load and high shock.......and different from other bearings. We probably have done about 80 of them over the last twenty years. They are expensive to do.......about 5 grand a box. But when done with the upgrades, they steer like they have power steering. With the modern seals and o rings, we run ATF for a lubricant....that’s how tight and dry they are when finished. We also made new worms for the L-29 Cord with a higher ratio to make steering easier......you turn the wheel in parking lots more......but it turns like it has power assist standing still. We also did right hand drive worms........it was an interesting project. We also made a box for a well known and famous Duesenberg from scratch.......and it came out good enough to make first in class at a Pebble.......not too bad considering.

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Edited by edinmass (see edit history)
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Here are more photos of the boxes. You can see where we grind the sector down to ride on Torrington bearings and machine the box for the seals and bearings. We also grind the races off the factory worms and use a new race and bearing designed by Timken for steering box shocks and loads. Grinding and heat treating along with keeping the tolerances were an ongoing nightmare. We had a bunch of engineers involved and signed off on everything.........it’s very easy to get ahead of yourself making parts that are unsafe. And you can not take short cuts on a steering box. In the end, it all came out well......and we were proud of the results......they ended up in some fantastic cars that were not drivable for years due to box issues. It was fun being able to drive some of the automotive legends we did boxes for.........

 

Unfortunately today, Timken no longer makes most of the bearings we were using, we bought all available stock from all over the world, but we are now running low......and the project will end with hundreds of cars that won’t be able to be repaired.

 

 

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Edited by edinmass (see edit history)
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2 hours ago, edinmass said:


On a worm and sector or lever I agree you can move the box from the wheels with it jacked up. I’m not sure you can do it on an acme thread and nut..........my guess is it would depend on the ratio. 

 

I have never encountered a 'Acme thread and nut' steering system, but I have many acme precision systems on my machine tools (lathes and mill). I tend to agree with you as the acme threads are a square profile and offer much more resistance to movement. One question about this type of steering system...  When you leave a turn, do the wheels return to strait if you release the steering wheel? I think that would tell a lot about being able to move things by hand.

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@edinmass, I just looked at the box pictures you posted. All I can say is WOW!!!   Absolutely beautiful work!!  It is a shame that after all the engineering and proof work, the bearings are now out of production. This must be heartbreaking.  It is people like you that keep the hobby alive. Please keep it going!!!! 

Edited by 37_Roadmaster_C
missing word (see edit history)
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The Acme thread boxes I have driven were rather early, and I can not vouch for them being set up correctly. Also, they were mostly museum display machines from what I can remember......usually not well sorted cars. It’s the alignment that pushes the wheels to return to natural.......so I expect that you may need to turn the wheel into and out of the corners. 

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1 hour ago, 37_Roadmaster_C said:

One question about this type of steering system...  When you leave a turn, do the wheels return to strait if you release the steering wheel? I think that would tell a lot about being able to move things by hand.

Your question was answered in an earlier post by the OP.

"The steering difficulty is evident while making turns in motion, not just while stationary. As I mentioned before, the steering does return straight after a turn without having to crank it back. This one thing would seem to indicate that maybe the steering is operating properly"

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Well the saying "steers like a truck " may have come from there. The kingpin system with the washers is pretty basic. Make sure there is grease getting between the washers are they likely have a pin so that one turns with the spindle and the other doesn't. My 29 IHC is not bad when in motion but there's no turning it stopped. 

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18 hours ago, Oldtech said:

Well the saying "steers like a truck " may have come from there. The kingpin system with the washers is pretty basic. Make sure there is grease getting between the washers are they likely have a pin so that one turns with the spindle and the other doesn't. My 29 IHC is not bad when in motion but there's no turning it stopped. 

Thanks. Can you tell me what the steering ratio is on yours ? That would be the ratio between the number degrees on the steering wheel (turns times 360 ) relative to the number of degrees that the wheels arc. 

I loosened the top to bottom clearance on the kingpins (it was zero), put 90W oil in where the washers are located, then alternately jacked up and lowered the axle, theoretically giving the lubricant an opportunity to get in between the washers. Pretty remarkable really, to put the entire front end weight of the  truck on two 2 1/2" washers. That's not much surface area. The designers knew more than I do, however, so who am I to question their work. 

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20 hours ago, edinmass said:

The Acme thread boxes I have driven were rather early, and I can not vouch for them being set up correctly. Also, they were mostly museum display machines from what I can remember......usually not well sorted cars. It’s the alignment that pushes the wheels to return to natural.......so I expect that you may need to turn the wheel into and out of the corners. 

Edinmass,

       I'm greatly impressed by your work on steering boxes. Clearly, you know what you are talking about. Thanks for your helpful advice.

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