Rear Shackle Install On A '40

[philipswanson]

Yes, the wagon spring is much heavier. It was built as a commercial vehicle in those days.
The spring mounts perfectly parallel with the car body but the axle housing arms are not. Twisting that spring does not work. Will be focusing on the arms and not the spring. First to disconnect the remaining radius arm and twist differential. If that doesn't work, out comes the torch. Thanks for all the help!

[Mart]

I'm not quite sure what you are proposing, but the axle housings, bolted together are very strong. the radius arms are there to protect against shock loading as a wheel hits a pothole, kerb or other thing that could cause the axle to get bent. (by axle I mean the rear axle assembly not a shaft).

Removing the radius rods will not turn the axle housings to jelly and miraculously suddenly allow you to slide those shackles in place. You won't bent the axle. You would do better to identify the perch that has a problem, apply heat and straighten it.

Once straight, turn your attention to the spring. If it is so stiff that you cannot adequately stretch it to fit, then either get a stronger spreader, or start looking at whether the spring needs to be that stiff. Have extra leaves been added? Do you need the full load carrying capacity? You could look at replacing the centre bolt with threaded rod, and relieving some of the load on the spring. (use clamps as a safety measure, be careful).

Lots of ways to go about it, it can be done, but unless your perches are dead straight and parallel, even if you can get the shackles in, they will be on a bind and will probably wear oddly or prematurely.

If what you are doing isn't working, try something different.

Mart.

[JSeery]

Originally Posted by philipswanson

First to disconnect the remaining radius arm and twist differential. If that doesn't work, out comes the torch. Thanks for all the help!

How is that possible? Any additional input on what you are attempting to do?

[ford38v8]

OK, I have to add my two cents here now that you're considering putting a torch to it.
Don't do that please, that's way over the top wrong. Several ideas here:
First, You've only provided 3 almost identical pictures for us to go on, but from those, I'm thinking you may have the wrong shackles, too short, and the spring eye may be touching the shackle arm, which would prevent proper alignment: Check the distance of the shackle pins center to center, against the spec.
Another idea, you said you've adjusted the spreader to the point that you're afraid it will be overstressed. Back off and eyeball both shackle bars, to determine their positions in relation to each other. You may have one pointed up and one pointed down, or otherwise misaligned. They should both be relatively in the same position opposite each other, pointed generally down. Think of your knees, if one was overextended backwards, you'd be so locked up you couldn't move at all. With only one shackle in place, the other loose, adjustments to this position can be made easily with a wrench or a hammer, or a pryer, or up/down with the jack, or with the spring spreader.
Lastly, by making those adjustments, you can bring the unconnected shackle together so perfectly that the pins will go in by hand with almost no force required. Yes, there will be a slight mismatch of the pins on the other side, which will require some finesse to get the bar on the pins, but if the correct adjustment on distance is made before putting the pins in place, it should require a minimum effort to get it together.
Again, this is the sort of a job that one can be thinking muscles can do it, but in fact, what it takes really is to take a step back and get your head around the problem, because it should never in a lifetime have to be so difficult as to require a torch to assemble! ...And no, don't disconnect the radius rods, that would be putting more obstacles in the way of proper assembly.

[19Fordy]

Philip: You sure are getting lots of input. That's good. As has been said before, best bet is to lower the entire rear end with the spring out of the car. Then try reinstalling the spring. Then raise the entire rear end assembly (with spring attached) back up into the cross member and bolt it in place. Please keep us posted.
As was mentioned, are you sure you are using the correct size shackles?
What is the center to center distance between the shackle pins?
I can't measure mine, but perhaps someone else can.
Are station wagons and cars the same?
Wish you could borrow my bullet proof spring spreader.
Hang in there.

[19Fordy]

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Attention folks: Here is the latest photo from Philipe that was attached to message below. Let's keep thinking this one through.
Personally, I am now wondering if shackles are correct distance between pins. Can someone please tell us what the correct measurement should be for a station wagon? Also, if the springs was not bolted to the U-Bolts, you could manually position it so the eyes were parallel and in-line with the housing holes. That would permit easier install of shackles.

"Still having problems with these shackles. Can you post another picture for me. I think this one shows the misalignment better. Looks like I am going to drop the spring again. It's so far off that if I drive the pins in, the plate is off a half a hole!"

[philipswanson]

Originally Posted by 19Fordy

Attention folks: Here is the latest photo from Philipe that was attached to message below. Let's keep thinking this one through.
Personally, I am now wondering if shackles are correct distance between pins. Can someone please tell us what the correct measurement should be for a station wagon?

"Still having problems with these shackles. Can you post another picture for me. I think this one shows the misalignment better. Looks like I am going to drop the spring again. It's so far off that if I drive the pins in, the plate is off a half a hole!"

These shackles are from Speedway and are the same distance apart as the stock ones I pulled out. As you can see in the picture, the upper lug (axle arm) is at a way different angle than the lower lug (spring). It is off so far that if I knock it in the nut plate on the other side is off a half a hole! I could drop the spring and attach that way (maybe) but no doubt I would be putting a major bind on the bushings. The problem doesn't appear to be the shackles but rather the fact that the two lugs are not perpendicular but rather at different angles. The lower one (spring) is at square with the car. The other one is going up hill toward the front of the car.

[Mart]

Ok, Phil, I'll have one more stab at this. The spring is square to the floor or the car, or the world or whatever. The axle is pointing up or down because it is hanging down and as a torque tube, it takes on an angle the lower it goes.

If you remove the spring from the crossmember, it can take on the same angle as the axle. (leaning back at the top). At this point you can make all the angles match and get the shackles in by knocking, levering, swearing,whatever it takes.

Once the spring is attached to the axle, the whole axle/spring assembly can be jacked up and mated back into the crossmember. the spring will hit the rear of the crossmember and will need to be levered forward to get it into the crossmember.

Once the spring is in place and the u bolts fitted, the weight of the vehicle can be placed back on the axle.

Here's the important thing, with the weight back on the axle the spring and the axle perches will now be in line. No binding.

If you still have the spring fitted into the crossmember, that is why you can't align anything.

If not, the problem must lie in a bent perch, or something like that.

Mart.

[19Fordy]

Phil: Here's a few more thoughts. According to my 40 Ford books, the 1940 station wagon 14 leaf spring is Part # 01A-5560-G. it cost $10.25 in 1940.

On my car with the tires sitting on the ground and the full weight of the car on all tires the distance between the OD of housing the eye and the OD of the spring eye using a pair of inside calipers 1 1/4 to 1 5/16 in. I notice your photos show a much smaller distance.

I think, if the shackles are correct size the arc of swing should replicate this same distance. Am I incorrect? When I made my shackles I made sure the distance between pins was the same as the OEM shackles and the pins were the same OEM dia.

PS: After reading Mart's theory (above) and the statement that the shackles are correct, I think he has the best solution so far. In addition, the spring clips may exert a twisting motion on the spring leafs when the spring is all by itself and totally free of the U-bolts. Then, as Mart suggests, after you attach the spring to the housing eyes and bolt it back in place inside the X member the twist dissipates.
Try Mart's idea first.

[philipswanson]

Originally Posted by Mart

Ok, Phil, I'll have one more stab at this. The spring is square to the floor or the car, or the world or whatever. The axle is pointing up or down because it is hanging down and as a torque tube, it takes on an angle the lower it goes.

If you remove the spring from the crossmember, it can take on the same angle as the axle. (leaning back at the top). At this point you can make all the angles match and get the shackles in by knocking, levering, swearing,whatever it takes.


If you still have the spring fitted into the crossmember, that is why you can't align anything.

Mart.

I disconnected the U bolts so the spring is just hanging from the crossmember on a chain. This allowed the spring to drop but not enough side play between the spring and crossmember to allow the spring eye to be at the same angle. With the spring hanging, I still have that mismatch because the spring hits the crossmember before aligning with the axle housing eye hole. It's a tad better but still not perpendicular to allow the shackle to pass through the bushings.

[Mart]

You need to get the spring in free air so it is unimpeded while trying to align it.

[19Fordy]

Mart is 100% correct. No interference at all. Once that happens, it has to fit.
I removed both rear wheels so there was more working space. You can bolt on some spare rims if you have them, but it's not a must.

[ford38v8]

Phillip, I agree, seeing the latest picture posted by 19Fordy, that your alignment is so far out that it won't assemble correctly no matter what.

As you have removed and replaced one axle housing, it looks like you may have mistakenly mounted it to the center section by one bolt hole off, an easy mistake to do. If that is the case, then that housing will be turned 36º differently than the other, making it impossible to align the spring to both shackle mounts, whether mounted in the car or dismounted away from the car.

Before doing anything else, just eyeball from one shackle mount arm to the other, see if they both point in the same direction, with the shackle mounting holes both being parallel to each other and the torque tube.

[19Fordy]

The one-bolt off theory would be such as obvious mistake. Nothing else would bolt up and rear radius rods would be way out of position.

[philipswanson]

Originally Posted by ford38v8

Phillip, I agree, seeing the latest picture posted by 19Fordy, that your alignment is so far out that it won't assemble correctly no matter what.

As you have removed and replaced one axle housing, it looks like you may have mistakenly mounted it to the center section by one bolt hole off, an easy mistake to do. If that is the case, then that housing will be turned 36º differently than the other, making it impossible to align the spring to both shackle mounts, whether mounted in the car or dismounted away from the car.

Before doing anything else, just eyeball from one shackle mount arm to the other, see if they both point in the same direction, with the shackle mounting holes both being parallel to each other and the torque tube.

No, they are mounted correctly. Wish the fix was that easy tho.

[philipswanson]

Originally Posted by Mart

You need to get the spring in free air so it is unimpeded while trying to align it.

The only thing impeding it is the shackle on the other side. It took me a day to get that one bolted up. If I take it off too, I will have two that are misaligned. But I willing to do it. The passenger side is the worst misaligned so I guess I should do that side first. Will give it a try. Thanks!

[Ggmac]

I thought that the front shackle length is 1.5" and the rear is 1.75 or even 2" . I just removed 2 rear springs one a 41 and the other a 46 , both had longer length than 1.5
They were both bubba ized in its past so who knows what was done .

[Tinker]

rears should be a 2" spring? I don't think the shackles or bushing are the issue. It can be a interesting job.

[rich b]

I've come across a few stubborn ones in the past. First I break the edges of the shackle pins so they don't tear into the bushing, then put a bar on the back side and push the shackle in with a C-clamp, watching that that the pins stay pressed in place ( if any starts to come loose, tap it in as you push the shackle in place), once the shackle pins contact the bar, switch to a bar that will clear the shackle pins and pull it in the rest of the way with the C clamp, then use a water pump pliers to squeeze the shackle pins together enough to start the inner plate over the studs, release the pliers, and pull the inner plate on the rest of the way with the C clamp, put the nuts on, and you're good to go.

[19Fordy]

Phil: I just crawled out from under my 40 Ford coupe. The front spring shackles measure 1 1/2 in. between the center line distance of the shackle pins.
My rear shackles measure 2 1/2 inches between the center line distance of shackle pins. That extra difference would make your install a lot easier. My rear spring is 2 1/4 in. wide.

I replaced the rear OEM shackles in early 70's with one's I made in my school machine shop where I taught. I made the end plates (bars) out of 3/8 in. thick steel as that's what i had to work with. I was very careful to get the centerline distance correct. I am sure the car rear end was original when I bought it as I knew the history of the car.

I just looked in the BIG GREEN BOOK (page 182) and it says that the shackle end plates (They are listed as "bar") used on (Pass 1932-40) (Comm 1932-41) (Trucks 1935- 37) (122" Truck 1938-39) are Part # 91A 5468-A and measure 1.56 inches between shackle pin centerlines. They say that 8 are required and that they are used for both the front and rear shackles (1932-41). Like I said, I found that not to be true on my car.

That doesn't make sense to me. Did Ford make larger shackles for the rear at some point?
My car has 1939 glass and push-in and up ashtrays which makes me think it's an early production car.

If so, it appears that your shackles are the wrong size as compared to mine. It would be good if another Fordbarner could measure his rear shackle pin distance. I don't know where you would get 2 1/2 in. shackles. These shackles have been on my car for decades with no problems. The rear 2 1/4 inch spring is stock OEM. You can see in the photo that the car "sits" fine (when it was restored) before I changed to 15 inch wheels and a dropped axle.

I know this sounds crazy but at this point I would cut your shackles and weld them together so that they are 2 1/2 in. between pin cenerlines and install them for a trial fit.
If they fit, make a new set for permanent installation. This means more work but just take it a little at a time.

Also, send me a photo of your spring spreader under pressure on the spring. Is it possible that your spreader maynot be adequate for the job and is actually bending causing the spring eyes to be canted? I will post the photo for you.

I hope Mike Kubarth chimes in. Perhaps Ford make parts not listed originally in their books.