VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 shackle replacement

I am going to replace one of the shackles on the rear of my 31 truck frame. What do I need to watch out for? Should I be taking weight off of the frame or spring? Can someone give me some advice?

Support the frame and lift it almost to the point of raising the wheel so that when you remove the shackle the spring stays in the same position. The pins in the spring ends should be replaced if they are worn.

31 truck: I replaced the left rear shackle on my '31 1/2 ton a few months ago. I'll tell you what I remember:

The pin on the spring eyelet side had fatigued (from lack of/and or improper lubrication) and had broken, and the weight of the truck was resting on what was left. The whole thing was jammed together as a result I jacked the back up by the frame and let the spring drop as far as it would go (it was jammed, so it didn't clear the shackle even when it was raised all the way up).

There is a bushing in the spring eyelet that needed to be punched out. I didn't want to remove the entire spring, so I tried pressing the bushing out with a nut/bolt/washer/socket combination. This didn't get me anywhere very fast, so I decided to go after it with an air chisel with a punch shaped bit. The bushing walked right out with a 6 to 8 second blast. I think I lightly hammered the new one in and bumped it from side-to-side to center it.

I decided not to mess with the pin in the frame end because I hope the truck isn't going anywhere before I get a chance to go through everything. I just didn't want it setting on a broken shackle for several more years (but then, what would it have hurt?)

Where I went wrong was I greased the pin... Chevy Chip says to use oil, if you check on this site you'll find a posting where I was seeking help with a similar problem on my '37.

Do you have the replacement shackle yet? I had a little difficulty finding one, but then again I didn't belong to the VCCA and this chat site was not on-line when I was looking for mine. I finally found two sets (they are interchangable RH to LH) at Obsolete Chevrolet.

BTW: This is the kind of information that we need to find a way to capture in a better way than someone remembering a thread, then someone else trying to find it. I'm hoping I can help solve this problem someday!

Grumpy Lenn
Thanks for the instructions. I printed the out so I can study them prior to beginning this operation. I found a shackle set on ebay. The woman that I purchased them from had several sets, but I only purchased one. I was hoping to find them at a later date a little cheaper, than what I paid for this one set.
I worked on my truck alittle more this weekend, so I should send in another picture to update the last one. I have been working on attaching the cab...I had to cut off every bolt to attach the cab to the cowl.

It seems that no matter what I do, I end up paying too much for anything... I don't remember, but I think I paid over $100 for the two pieces, and they must of been NOS because they were un-worn but rusty, like they were exposed to humidity. We don't have much humidity here in Salt Lake City, so things get preserved well.

It's just for fun anyway...

Lenn.

I am now in the middle of this replacement, and have beat the pin out of the spring. Any good ideas of how to get the pin out of the frame? I tried everything but heat. Is heat OK to use?


Slow. but unsure

If you have the capability, I suggest you use an air hammer. The jarring sometimes assists in getting things on the move.

31,
You may have to use both the pneumatic (air)hammer and thermal wrench (torch). A little heat will not hurt. Just warm it a bit, don't get it red hot. If you are timid use a propane powered wrench so you can't get it too hot. A piece of SAE allthread a couple of large washers and nuts inside a 6" piece of pipe makes a good puller installer. Lubricate the threads and thighten with the air wrench. I have also used a long fine thread carriage bolt like used to hold the bed on a 3/4 - 1 1/2 ton truck. You might have to grab the head with the vise grips to keep it from turning. Just don't think about the 8 lb maul (sledge hammer for you younger fellas).

Hey chevy chip
I was not too timid on this....although I have already beat it to a pulp and it still doesn't want to move. I will try the blue wrench when I get the chance, I am afraid that I will have to cut it off and convince the rest of it to be drive out the other side. I am sure I have already mushroomed it enough that it won't be easy.

Hi 31 truck.

Sorry you are having trouble with this, like I said, I used an air hammer, and the pins came right out.

Do you have an air compresser? If so, air hammers and ear muffs are really cheap, and will get you out of a bind so you might consider buying one of each.

Well no air hammer in the tool box, but by tonight there will be. I borrowed my brother's, he said it didn't too good....he was right. I spent more time attempting to repair his than working on the pins. haha
I report again tomorrow on my progress. It is a good thing there is no audio with the pictures I am taking of my restoration procedure....I would be banned from the site.

Good Luck, I hope the air hammer works since talking them out doesn't seem to!

Bad news
air hammer broke them off.

Too late for me to delete my post recommending the use of the air hammer.

Where can I buy some C4? That will probably shake these pins loose!
Anyone else have any ideas?
I might have some parts for a 31 1/2 ton pu truck for sale......anybody interested?

Ditto on my post for the air hammer. :o :o :o

Your truck must have spent some time at the bottom of a bay somewhere? Can you post pictures so we can see what damage we have caused? If you can't post them, send them to me and I'll give you a hand.

Did the pins break or the forged frame ends? If it is the pins no big problem. If the frame ends, problem! If you warm the frame ends the pins should come out with mild persuasion. You may find it necessary to heat and quench with water a few times to break the bond. If that does not work then cut them out with a cutting head on the torch. Or heat the pins to a dull red and quench them. That should make them brittle enough to break them into pieces. You may need to use the trusty cold chisel and hammer to not mess stuff up too much.

As my grandpappy usta say. If it don't come, get a bigger hammer, if it breaks it needed fixin anyway.

Thanks for replying....If I sound frustrated you have got it. Actually, I can't believe the forged end hasn't broken. It is the pin in the frame end that has broken off. On the passenger side, outside edge, I have this one polished down to the end of the forged end, the other end, inside, is still the normal length.
I will have to borrow a torch, and try the heat/quench procedure.
Thanks again.

On my 1930 sport coupe, I had a heck of a time getting the shackle pins out on the frame as well. Tried everything, including heat from a torch and the pins still would not budge, and the pins were not rusted either. But, they sure didn't want to come out. It was kinda sorta like they were welded in place, but they weren't. Fortunately, at that time the car was already stripped down to the bare frame, so I took the frame to a local machine shop that had a big, big hydraulic press. Three of us wrestled the frame around and put it in the hydraulic press. Heat was again applied and etc. and then the press went to work. As I remember, it took anywhere from 12 tons to over 20 tons of pressure to get the shackle pins out. Two of them, under full pressure, would not budge so we just left the frame in place under full pressure. Shortly, they shot out like a bullet from a rifle. While there on the press, we pressed in all new shackle pins and they went in very nicely. What a job that was! :eek: :eek: :eek: :rolleyes: :rolleyes: :rolleyes:

I don't know if I have that kind of perseverance, and I really don't want to find out...

question for 31 truck. I learned a new term but don't know the meaning. Please help. Does a "blue wrench" mean creative language that makes the air blue??

I bet that means the blue tip flame from an acc/oxy torch, just to give morality the benefit of the doubt!

Mr. Mack is right....We used to call the torch a blue wrench in high school shop, just to let the ag teacher know, that if we couldn't get it loose any other way.......we were going to torch it. He didn't like that alternative, because it was too easy..... I having never had torching experience until high school, and having beat many a finger thumb hand and arm with a hammer while drawing a bead on the end of a cold chisel...the blue wrench certainly sounded like a fine idea to me.

JD...... I feel really sorry about that frame problem you had. I have got to tell you I have beat this pin almost sideway. I sure hope the flame does it.

The flame didn't do it for me, so thus the big hydraulic press. It was a headache hauling the bare frame to the machine shop and getting it to fit in that press, but it worked and I was a very happy camper after that!

Blue wrench? I have several old wrenches that are painted blue! I even have a red wrench too! :eek: :eek: :eek:

... I had a red-headed wench, once, my self, meaner than a junkyard dawg!