Rear Axle: Rear axle diagnostic assistance please

[Champion51]

I am about to take on a major undertaking with my rear axle. Have never taken an axle apart and in general have very little mechanical experience. So I'm feeling very apprehensive about this diagnostic search for the problem. and really worried that I may be opening a can of worms. If I can't get it back together, well ....... you know the rest of the story!
Non of our local mechanics are interested in working on a 60 year old car let alone a Studebaker. So, I'm out here on my own.

I am getting a clunking noise at slower speeds and I had thought it was a centre shaft bearing issue. However, with the car up on jacks, and rocking the right rear wheel back and forth, I can hear a clunking sound of a loose metal object coming from the hub area.

Before I start ripping her apart, a few questions that may help relieve the apprehension.
I have searched youtube for any instructional videos on this issue, but it appears there are none. Darn!!!
A while back an old timer came around to install new brake shoes. I did not have a hub puller at that time, so he proceeded to apply high heat to the axle (or hub, can't remember) and then bang on the rear edge of the hub till it finally popped off. My first question. Is it possible or likely that while trying to free the hub, that the axle was "un-set" from the differential? This came to mind after having read the thread yesterday about loose end play in an axle by t1003nl. If so, could the problem be resolved by attempting to simply "re-set" the axle by tapping or driving it back into place?
Looking at the exploded view diagram in the manual, it is very difficult to really see how things work, so I'm thinking I should take the rear cover plate off the differential and have a good study the working parts. Would this be a good idea or not? I am looking at "page 11 REAR AXLE" of the manual. The exploded view shows only the right axle. Why haven't they illustrated the left axle? Also, I don't understand how the adjusting shims play into the picture and what their function is? Does the "lock pin" hold the "thrust block" in place and is the pin an essential part? (I have read stories about the pin becoming dislodged or even lost).
If anyone has any suggestions as to how I should tackle this or what the possible problem could be, I'd love to hear from you. I know there is a great resource of technical knowledge out there and I worry that as we all get older and move on to distant places, that this knowledge will be lost for good. I'd love to see more instructional videos on-line. If you know of any that I may have missed could you please drop a link in a reply to this thread. Thanks!

[r1lark]

Did you have the clunking BEFORE the 'old timer' heated up the hub to remove it? If not, you may want to start there. I would be concerned about heating the hub up like that. Also, the nut that holds the hub to the axle takes a high torque (on the later axles I believe it was around 170 ft-lbs, but check your manual for what your car requires). If the nut is not tight, you can get a clunking noise which comes from the hub moving on the tapered end of the axle.

[Bud]

You will get a clunk from the rear end if the brake drum hub is not tight. I've heated hubs to remove them in the past, but I don't recommend doing it unless the correct drum puller can't break the drum loose. That said, excessive end play on the axles due to improper assembly or worn wheel bearings may make noise, but I suspect you have a loose drum. The correct axle nut torque is 170 lbs.-ft or one pin hole on the nut past the 170 mark. Bud

[RadioRoy]

You should get a chassis parts manual also. It will have exploded views of all the parts.

Taking apart a rear end like this is something I would never recommend for a newbie, especially one who knows he is not good with mechanical things.

Answering r1Lark's question is vital. Did it clunk before the hub removal? If not, then I would leave the differential alone and look at the outer wheel bearings, the hubs, and the ends of the axles.

Actually, the first thing I would do is check the U-joints and the yokes on both ends of the drive shaft.

[Champion51]

Thanks for your ideas gentlemen. Paul, when you suggested that the axle nut nut make not be on tight, BINGO, the lights went on! When the old fella put the hubs back on couple of years ago, I distinctly remembered him telling me that when the nut is tightened, it is just taken to the snug position, then backed off a half a turn. He said the axle nuts should allow some free play. Guess he was wrong! And no, the car did not clunk along prior to the brake job. So it looks like we might have the problem solved. I'll get at it tomorrow and just see how loose that nut is. Don't have a torque wrench, but sounds like I need the big one to get that 170 ft/lbs of torque. The only other possibility, is the fact that we have home-made bushings (cushions) in the center support bearing, with the ends of the cushions making direct contact with the cross-member. With the car on stands and running in first gear, I can see the drive shaft is not turning completely true. So I'm glad you added that point Roy. Can you elaborate a little further and tell me what I am looking for when I check the U-joints and yokes and the ends of the axles? The only other question still unanswered, could the axle have been pulled out of place when the hub was hammered off? That one is bothering me. Thank you again, Paul, Bud and Roy. Stay tuned for the ongoing saga of "As the Axle Spins".

[jackb]

Let's make the assumption the old timer did NOT limit his errors to axle shaft nut tightnesss or hub pulling. You need to inspect things inside for his other work...

[Champion51]

With the hub cap off, I rotated the R wheel by hand. There was no reciprocal reverse movement of the L wheel.
Observing the exact placement of the nut on the R side, I compared to the placement of the nut on the L side. It appeared that the R nut was 1/6" to an 1/8" further on the axle shaft as compared to the L. The O/S face of the L nut was recessed only about a 1/16" in from the flat end of the axle.
And so, after removing the cotter pins I commenced to tighten the nuts. It appears that they were both a 1/2 a turn or so back from the tightest position they will take when torqued right down and that amounted to the pin being inserted on the 2nd or 3rd slot back from the the maximum slot available for insert. The position he had them in wasn't much more than finger tight, as you can only turn the nut about 1/2 of a turn or so tighter than that, to its maximum tightness. So, I took the nut to its maximum and then backed it off to the 1st available slot for insertion of the cotter pin in the castle nut on the L side. I noted that the R side nut had a good 3/16" of space from the outside end of the nut, to the face of the flat end of the axle shaft. The L side only had a difference of maybe a 1/12". Therefore it appeared that the R side axle was a full 1/8" (perhaps a 1/7") longer than the right. So, I backed off the R side nut until it appeared to have the same placement as the L. A gap of at least 1/7" remained between the back of the nut and the face of the large flat washer. I decided to tap lightly with a light sledge hammer, hitting the axle end squarely, and after about 4 good taps, was able to eliminate that gap. Therefore, the axle obviously moved. Don't know if I did a good thing or bad thing? I then tightened the nut to the point where I could use the last possible insert location for the pin, on the castle nut I then turned the wheel by hand and voila, the L side wheel reciprocated in the reverse direction. Had a good feeling about that. However I went back to the L side and turning the wheel the wheel clockwise I noted that the R wheel was hardly turning at all. Also noted that after several good hard turns the R side wheel would begin to turn, but it didn't have the same instant engagement as L wheel did when I rotated the R wheel.
The only thing I have not done, is tapped the L axle in the same manner as i did with the R. If I am able to move the L axle inwards say an 1/8", I think it will leave the face of the axle nut proud of the face of the end of the axle by 1/16" or so. And I don't know if this is a good thing.
At this point I really need to know if the axle could have been driven out of "SET" with the differential when he was wailing on the back side of the brake drums in an attempt to free them from the axle. The hubs were really frozen to the axles. I had read that the drums must not be hammered off, however my old friend (Sheldon), a mechanic for almost 50 years and having owned and worked on many Studebakers in the past, gave me the confidence to trust his experience and ability.
So if anyone can shed more light on the axle saga, would love to hear your ideas and suggestions. Thanks again.

[41 Frank]

You need to reread the advice that was given. You don't tighten the nuts so they look even from side to side. You tighten them to 170# and then go to the next available hole, if hole is not lined up. (tighter, not backing off)to insert the cotter key. The one wheel turning one way than the other means nothing, other than you have a non twin traction rear end.

[RadioRoy]

I would also make sure that the keys are not in backwards and jamming against the taper in the axle keyway. The key wants to go in with the taper in and towards the axle, so that the key taper and the axle taper compliment each other. And the key wants to be as far OUT, away from the axle and towards the nut and washer as possible.

If the keys are in backwards, or if they were inserted before the hubs were installed, then they could have ridden up the taper on the inner end of the keyway. That will block the drum from going on far enough, and will stress the end of the hub. Most importantly, that can stress the axle and cause the axle to break off while you are driving. I have had that happen to me and it can be terrifying to lose a wheel, and all possibility of stopping or slowing the car down.

That means removing the rear drum and hubs (with the proper puller this time) making sure the hubs are not damaged, and inspecting the keyways in the axle. When you put the hubs back on the axle, you should line up the keyways and push the drum/hub on as par as possible by hand. then insert the key in it's proper orientation, but no deeper than flush with the outside of the hub. Let the nut and washer push in the key so that is is as far away from the axle taper as possible.

The drive shaft carrier bearing should be mounted with the correct studs and bushings. They are available at Studebaker vendors.

The U-joints should be checked for play/looseness, and lubricated with chassis grease into their zerk fittings.