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I finally got to cruise my 58 down the street. Still working out some bugs, but what a great feeling . Which brings me to my current question. My Viking is a two ton with a two and a half ton front axle. The manual says to torque to 55 foot pounds while rotating hub and brake drum. Then, back off a 1/6 of a turn. In my attempt, I found at 55 foot pounds the castle nut is in line with the hole in the spindle. Rotated back a 1/6 of a turn per manual instruction to line up hole in spindle leaves a lot of play in the bearings. With the wheels mounted and on the ground, and rocking the top of the wheel back and forth, the play seems excessive . So, my choices are, leave 55 foot pounds of preload on bearings, or leave wheel bearings loose which seems excessive. Note that at approximately 40 miles an hour the steering wheel thrusts left and right which I am attributing to the loose wheel bearings. It is equipped with barrel roller bearings, which I just cleaned and repacked.

Rich

Rich,

Just thinking rather stream of thought here. Having 55 foot pounds of torque on the castle nut will overheat the bearings, and having play is also not a good situation. Have you tried swapping the castle nuts from one side to another? If you are real lucky, the cotter pin holes may be milled a little differently allowing a more reasonable preload.

Not a bad suggestion. However, the driver side castle nut is left handed thread.

Rich

Check the spindle closely with the nut removed. There is usually more than one hole for the cotter pin, which allows you to split the difference between castle nut slots. The holes are at a different angle than the slots, 90 degrees apart instead of 60, IIRC. If there's not a second hole, drill one.
Jerry

Hy viking58, well I learned something this morning, I have never seen a left hand threaded spindle on any Chevy truck I have ever owned or worked on, must be rare!

I’ve not seen left handed either.
GM had this wheel bearing adjustment figured out, you for sure don’t want it torqued tight, and they accounted for all possibilities and you can back it of as specified without backing it off to far.

I’m guessing two holes in spindle as Jerry suggests, second one probably full of grease.

If still looking for more possibilities check washer thickness and try another more or less if you have one, same idea as different castle nut.

If it's tight at 55 go back one castle slot, if that is 1/6 that's great, but one slot only. The initial 55 lbs is to seat and preload the bearing and should feel tight. (slight drag) If 55 is not tight, then just tighten until "tight" while spinning. (tight means slight drag when spinning). You must test wheel/tire OFF the ground.
It should be able to spin a few times with a hard push. It will loosen up anyway in a few miles. Recheck spin later. It should only move a very small amount. We are talking .005. You would barley feel it. You would not feel it with tires on the ground. If you have a lot of movement, it's not the bearings assuming you are sure they are not worn out, it's joints, steering parts or king pins or .....worse

Roller bearings may have a different torque value than ball. You did not say if you examined cones, cups and spindles carefully for excessive wear.

As a last resort, take a belt sander to the washer between the nut and the bearing, but don't grind your fingertips off in the process!
Jerry

I will take the nut off to see if there is another position other than 3 and 9 o'clock I am currently aware of. I completely cleaned spindle and bearings during the complete brake rebuild. Even went as far as to paint wheel cylinders, backing plates and dust shields. The spindle bearing and seal surfaces were in great shape. The barrel roller bearings and races looked great too. With the bearings at 55 lbs of preload and wheels on ground there is no more movement when pulling the top of wheel back and forth. So, I am going to rule out kingpins.
The left handed thread caught me by surprise also. I just assumed all were this way. I never have had a truck this big to compare or experience.
The idea of adding washers seems to be the best way to fine tune the adjustment.
What is surprising is the fact that at 55 ft lbs of preload the castle nut slot is almost in perfect line with the hole in the spindle. Turning back 1/6 of a six sided nut is one flat of the nut. So, I have only turned the nut back one slot, or one flat, to insert the cotter pin. If there is another hole available for the cotter pin the final adjustment will be less than 1/6 of a turn minimum per the shop manual. The difference in turning that nut back one flat is significant. I even checked my torque wrench to make sure it wasn't giving me a false reading. This is the same with both sides. This is a retired fire truck with less than 5000 on the odometer.

Thanks for all the suggestions,
Rich

Did you change any of the bearings or races or accidently mix the bearings from left and right, just throwing out more thoughts here. I would be inclined to shim the original set-up to get the free play you want. I'm working on a similar truck but haven't done the fronts yet, rear left spindle nuts are right hand thread but the Bud wheel nuts are left hand.

If there's not a second cotter pin hole in the spindle and you want to reduce the amount you need to back off after preloading, you could also grind/file/sand the castle nut a little to change the relationship of the castles to the spindle hole. That would probably be simpler than tinkering with the washer thickness.
Jerry

I did not replace any of the wheel bearings or races. I was also careful to make sure the bearings were mated with their original races . I just went thru my pictures and there's no second hole in the spindle.
I'm just spit ballin here, and since my truck is equipped with larger than two ton equipment, and a left handed spindle nut, what is the adjustment procedure for a larger truck like a 70 or 80 or 90 series? I know its a reach, I'm just looking for a good reason that the factory adjustment procedure wont work on my truck. If not, I think the idea of running the castle nut on the belt sander is the best alternative to change the relationship of the slot and hole in spindle.

Rich

Rich,

I believe the manual says to back it off 1/6 turn and if that doesn't line up for the cotterpin then continue backing it off to the next available castellation. Note, this is done with the tire and wheel off and by spinning the drum/hub only. As soon as you put the load back on the tapered bearings the play will be gone as they self center.

Mike B

Your correct Mike. That's exactly the procedure I used. I don't remember, nor did I pay attention to how much play there was in the hub when I took it apart. The difference between one slot in the nut seems excessive. However, this thing ran 5000 miles and the bearings and races look great. So, these bearings must have been ok with the loose clearance I am experiencing.

I'm sure in 1958 this was perfectly acceptable. These things didn't have to compete to share the highways with vehicles as they do today. Keeping up with traffic and stopping safely requires us to pay attention to these details in order to enjoy our old iron. I cant help but want to improve my truck to roll a little smoother and safer. These little details will make driving them much more enjoyable.

Sometimes we don't get the answers or the responses we are looking for when we post our questions. However, having an experienced group to bounce your thoughts and problems off of is enjoyable and comforting. The amount of knowledge on this site is unmeasurable.

I have been a member of this site over a year now and want to thank everyone for taking the time to respond to all my questions. I also want to thank the moderators for taking their time to keep us all in check.

I know I went a little off tangent, however it seemed like an appropriate time to give thanks.

Happy Thanksgiving to all and your families.
Rich

How about using a suitable size washer between the castle nut and special washer to change the orientation?

I am either going to go that route or belt sand the back of the nut to get the clearance I need.

Rich

Rich,

I'm currious...how much/little clearance do you think the tappered bearings need and what problems do you see in following the shop manual procedures?

I found this on Timkin's site;

"No special tooling, gauges, charts or fixtures are typically required, but assembler’s skill and judgment are necessary. For example, in the case of a
conventional truck non-driven wheel with a single adjusting nut design, manual setting involves tightening the adjusting nut while rotating the wheel until
a slight bind is felt. Then the adjusting nut is backed off 1/6 to 1/4 turn to the nearest locking hole or sufficiently to allow the wheel to rotate freely
with some minimal end play. The adjusting nut is then locked in this position."

Chevrolet/GM engineers have taken the guesswork out for what they concider bind to be by giving us a foot pounds of torque number (based on bearing size) for "preload bind" and then telling us to back it off 1/6 of a turn or more to line up with the hole (sounds like GM had Timkin write this procedure). This adjustment allows for bearing expansion as the bearing heats up to normal opperating temperature.

By sanding the nut or washer isn't that going to give the same result as turning the nut to the next available slot?

Am I missing somnething here???

Mike B

Mike;

IMHO. I think by sanding the nut or washer allows the nut to travel a greater rotational distance before arriving at the same clamping distance on the spindle. If the nut rotates farther then the castle nut projections/gaps have a better chance of lining up with the hole(s) in the spindle. This technique gives you a bearing pre-load that can eliminate the excess slop. I agree with you, in that one must still allow for expansion that occurs with heat etc. In this case, the OP is dealing with clearances that are excessive with the 1/6 turn technique.

SimS

There is a difference in adjusting procedures for Timken tapered roller and ball wheel bearings (and barrel shaped bearings?) Pretty sure ball wheel bearings are adjusted a little snugger than tapered roller, which are a little looser than snug.

What kind do you have?

I’d be a little concerned sanding the nut or washer, you should keep washer parallel and face of nut square to centreline of threads. Not saying either is a good solution. If absolutely required I’d trim nut on the lathe a little.

Looking beyond that I’m not so sure this adjustment is an issue, pretty sure it’ll be OK as GM explains how in service manual for that axle. Might be thinking to hard...

Given the manufacturing tolerances of at least half a dozen parts,- - - - -bearings, races, hub casting, spindle, washer, nut, etc.- - - -anyone who thinks a specific procedure dreamed up by an engineer who has little, if any real hands-on experience in a shop will work in every situation must be smoking some really prime quality weed! Sometimes common sense has to take over where blindly following the manual gives less than stellar results. There's nothing whatsoever wrong with a little careful tinkering to achieve the desired results in real life.
Jerry

Mike,
By sanding or grinding the back of the nut or washer I am trying to reduce the amount of clearance provided for the bearings when I follow the proper shop manual procedure. At the 55 ft lb torque, the castle nut slot is almost lined up with hole in spindle. Now I back off nut 1/6 of a turn, hole and slot line right up...perfect. No more, no less than manual suggests. With tire and wheel bolted on, and on the ground, I can push and pull the top of the tire and the hubs rock on the bearings. Enough that you can feel and hear the rocking of the hub back and forth. This seems terribly excessive to me. I have adjusted wheel bearings on cars and light trucks many times without failure. This is my first medium duty truck. The procedure leaves way more clearance than I have experienced on lighter vehicles.

My goal by changing the dimensions of the nut or washer is to be able to reduce the distance I back off the nut to less than a sixth of a turn. If I add a washer between the nut and existing washer, I will change the relationship between the castle nut slot and the hole in the spindle when torqued to the 55 ft lbs. This will allow me to back off the nut less than a sixth of a turn to the next slot in the nut. Which would reduce my bearing clearance. This could also be accomplished by sanding the nut or existing washer.

During my first few maiden voyages, I noticed a shimmy in the steering at approximately 45 miles per hour. After inspecting steering and front suspension I came to the conclusion that the rocking of the front hubs was the culprit because I found nothing else wrong. So, its not only my assumption but a mechanical issue that leads me to believe these clearances are excessive.

You have quite a stable of task force trucks there Mike, and experience is everything. Feel free to constructively criticize.

Earlier in this post it was suggested that .005 endplay is correct. I purchased a dial indicator to measure my current clearance before I attempt to make any change.

Thanks, Rich

The bearings are a barrel roller. The manual procedure is for a two and a half ton axle with tapered roller bearings.
If I hadn't experienced the steering wheel shimmy I may have not even paid any attention to the bearing clearance. Now that I'm aware, I cant help think that a fine tune will improve steering and handling of the truck, beyond solving a mechanical issue. I intend to drive this baby as often as I can. I hope refining fifty nine year old technology will make my truck more enjoyable.

I have been guilty of overthinking , some times a benefit, sometimes not so much......

Rich

Sounds like might be applying wrong procedure given the different bearing type.
First try to find instructions for wheel bearings like you have.

Jerry,
The stack up of tolerances isn’t an issue.
The adjustment procedure dreamed up long ago is based on thread pitch of the spindle nut and that pitch divided by 6, the six positions given by six slots in the nut.
I don’t know the pitch, but say for ease of math it’s 16 tpi, so one turn is 0.0625” and 1/6 of that is 0.0104” adjustment per slot.
If this was adequate then is still should be. Or perhaps there was a service bulletin put out with alternatives?

Wheel shaking when jacked up is a little different than play it may or may not have when on the ground, the tapered bearings with load tighten up.
Tapered bearings to tight and they heat, or heat in normal use and then get to tight if not left slack enough.
Probably more to understanding all the factors and variables involved than we may think of, “reengineering” without a full understanding might be asking for trouble.

In the end check how warm they are after an extended drive, slack off adjustment if necessary.

Ball or barrel rollers I’d guess (but might be wrong) need to be more snug, so the rollers fit matching shape in the race.
Tapered rollers (Timken) fit the straight profile in the race at a range of adjustment.

Only manual I have handy that covers ball, tapered, and “spherangular” front wheel bearings is the 1953 GMC 100-400 maintenance manual.
Ball and sphearangular are treated the same and are different than tapered roller:

Torque to 33 foot-pounds while rotating hub. (40-55 for tapered rollers)
Back off nut at least 1/6 turn and not more than 1/4 turn.
With brakes released and not dragging grasp tire at top, pull back and forth. If bearings are properly adjusted movement of brake drum in relationship to backing plate will be barely noticeable and wheel will turn freely.

I'd like to add a bit of experience here .

On my '40 , I have some wheel movement . I thought it was the bearing adjustment as I have done the kingpins.

After fiddling around for a bit (with the bearing adjustment ) I discovered that the outer bearing location (diameter) on the spindle is a little under size , just a few 'thou. But it is enough to give a deceptive reading of wheel movement at the outer dia of the tyres even with the bearings fully tight.

Grigg,

The 1958 service manual instructs only the 2 1/2 ton be torqued to 55 ft lbs. Ball bearing equipped hubs, back off to nearest slot alignment is obtained . Tapered roller bearings, 1/6 of a turn minimum until slot alignment is obtained.

I made the assumption that my barrel roller bearings are what is referred to as tapered roller bearings in the service manual. There is no instruction for barrel rollers, just ball and tapered bearings. If barrel roller bearings have a different procedure that could be my issue.

Hopefully I will get a chance this morning to go take some measurements.

Rich

Maybe we should confirm you have the correct bearings in place...what is the bearing part number?

I'm also not aware of barrel type bearings being used as wheel bearings. I always thought they were one piece bearings that couldn't be taken apart...am I wrong?

Mike B

Mike,
On my old WW2 Chevys, the barrel type Hyatt bearings were original equipment on all of the wheel bearing applications. I am not so sure about these "new" 50's model trucks.
Paul

If anyone is interested in actual manufacturer-sponsored research instead of quoting moldy old service manuals, I'll tell you about a project I participated in with a bunch of other trade school instructors in cooperation with the GM training center in Memphis Tennessee. Some of the early disc brake systems in the late 1960's and early 70's were experiencing brake shudder and uneven disc wear. In a research effort that included trade school instructors from several states, (including my father and me) it was found that putting approximately 60-72 inch/lbs. of torque on the spindle nut eliminated the shudder and improved the wear characteristics of the discs. The previous "tighten- - - -then back off") procedure appeared to be the cause of the problem. I see no reason something similar might be happening here, and sanding/grinding the nut to reduce the amount it needs to be backed off to get a cotter pin installed should be a viable solution.
Jerry

I was finally able to get out and work on the truck today. Its surprising how you remember something so vividly, and your memory plays tricks on you. Well, I was incorrect about the front bearings. They are a tapered roller bearing. It is the rear axle bearings that are a barrel shaped roller bearing.(I confirmed this thru the younger mind of my son)
I have decided to try and just snug them up and not to leave any play in the bearing as in Jerry's example. Take a short ride. and check the temperature of the bearing. I know this is larger than a light duty car or truck, but we never left any endplay in a front wheel bearing. Snug it up till it drags and loosen just enough to turn free.
Thanks again for all your input and suggestions.

Rich