Leaf Spring Getting Hung Up on Shackle

[Dan Salvin]

One of the leaf springs on my 14" trailer is getting hung up on the shackle. The spring seems to still have a enough bounce but when I go over a large bump, I can hear it click into the shackle and get stuck. I have posted a before and after picture below. When I pull up on the trailer, it pops out and goes back to normal. Is this a sign that the springs should be replaced? Should they not bend enough to allow this to happen or could this just be cause by rust on the spring and inside the shackle? Thanks.

 

[ajgraz]

Re: Leaf Spring Getting Hung Up on Shackle

The shackles are supposed to have a slight forward tilt to them, not a backward tilt as in those pics. Either the spring has lost it's spring, the spring is too long, the shackle mount (at the trailer frame) is too far forward, or the spring's front mount is too far backward.

What's the other side look like? Does the shackle tilt forwards or backwards? Are the shackle and front mounts in the same relative locations? Are the springs the same length?

 

[Dan Salvin]

Re: Leaf Spring Getting Hung Up on Shackle

I was reading an earlier post that said the shackle should have a slight backward tilt on a single axle trailer such as this. The shackle on the other side also has a backward tilt and I'm fairly sure these springs and shackles are original to the trailer. The mounts and shackles are in the same location on the other side. Thanks.

 

[ajgraz]

Re: Leaf Spring Getting Hung Up on Shackle

OK after researching this some more on the webz, it seems that a little forward angle on the shackle will give a stiffer "ride," a little backwards a softer ride, and any of that can be "correct" depending on the ride you want.

(Every single-axle trailer I've seen has the shackle a little bit forward-angled)

But clearly there is something wrong with what you've got going on there, if it's binding. Either the spring is shot or it is too long or the rear-angle is just too much.

Or perhaps, as in your other thread about the fact that your axle seems bent or "arced," the spring is bending sideways and causing the binding?

 

[Dan Salvin]

Re: Leaf Spring Getting Hung Up on Shackle

Thanks. Would you recommend replacing both springs with shorter springs to reduce the angle? Is it ok to put shorter springs on?

 

[Allbutwet]

Re: Leaf Spring Getting Hung Up on Shackle

I would would give those shackles a good dose of wd-40 or what ever penetrating oil you have. They look pretty rusty and probably just sticking. It looks like there is still a pretty good arch to those springs. Might even be a good Idea to take the shackles apart and inspect the bolts. Typically a leaf spring will flatten out over time as they loose their spring. If there is no cracks or other damage you don't need to replace them.

 

[jeeperman]

Re: Leaf Spring Getting Hung Up on Shackle

Thanks. Would you recommend replacing both springs with shorter springs to reduce the angle? Is it ok to put shorter springs on?

Look at both pictures closely. Both pictures show that the bushings in the trailer frame bracket as well as the spring eye are very worn or gone.
Notice how far the pivot bolts are off center compared to the parts they go thru.
Your pivot bolts might also be worn half gone if the bushing has not been there awhile.
If both bushings and both bolts are worn, it compounds the problem. allowing the spring to end up in the wrong spot easier.

Is the problem shackle on the passenger side where it gets more pounding from excursions off the shoulder of the road?

Your obviously getting lots of springy action of your suspension, at least until it comes down on the wrong side of the trailer bracket.

Those shackles are on the backside of the axle, right?

 

[Dan Salvin]

Re: Leaf Spring Getting Hung Up on Shackle

Yes, the shackles are on the backside of the axle and yes, the problem side is the passenger side. It sounds like the best course would be to replace the shackles, springs and all the hardware. Is that what you would recommend?

 

[jeeperman]

Re: Leaf Spring Getting Hung Up on Shackle

Yes, the shackles are on the backside of the axle and yes, the problem side is the passenger side. It sounds like the best course would be to replace the shackles, springs and all the hardware. Is that what you would recommend?

The spring appears to still have spring in it as the shackle is at a nice angle. If the spring was weak, the shackle would be more horizontal towards the back of the trailer.
I would for sure replace all of the bushings. There is one in the front and the rear spring eyes and the one in the rear frame bracket.
When you get it all apart, you might find that the spring eye and frame bracket bushing bolts are worn and need new ones. The bolt holes in the shackles might be worn bad too.
Spring steel is pretty tough, so I do not think the spring eyes would be worn so much that they would need to be replaced.
You will likely need new u-bolts that hold the axle to the springs unless they come apart without twisting the nuts off.
When you unbolt the spring assembly from the axle, check each spring leaf real close where the center bolt goes thru the middle of the spring pack.
Leaf springs are notorious for cracking in half and the crack will be right thru the center hole. When it is all bolted up under the trailer, it is hard to tell there is a crack in a leaf.

 

[j_martin]

Re: Leaf Spring Getting Hung Up on Shackle

Bottom line, you probably don't need springs, just shackle and pin kits. (Bushings and bolts)

my 02
John

 

[Dan Salvin]

Re: Leaf Spring Getting Hung Up on Shackle

Thank you very much for your help!

 

[Silvertip]

Re: Leaf Spring Getting Hung Up on Shackle

Angling the shackle forward will "bind the spring so it cannot move upward the way it is supposed to. Besides, angling it forward increases the chance of doing exactly what it is doing now. Besides wear, it is the rebound from a bump that is causing the axle to drop as the trailer frame rises. This causes the shackle to go straight down or slightly forward. When the frame comes down, the shackle flips forward and locks. So either there is excessive wear or the springs have indeed lost their tension. You can look at hundreds of trailers and you will not find the rear shackles slanting forward (unless you consider the top the shackle pointing forward) so lets make sure we understand each other. For clarity, the bottom (spring end) fo the shackle must angle rearward. The angle on this shackle is correct. Going farther back will limit its function because it will hit the frame on severe bumps.

 

[Dan Salvin]

Re: Leaf Spring Getting Hung Up on Shackle

Ok. Thanks. I understand. I am going to replace the shackles, springs and hardware with the same size of everything since the existing hardware and springs are the original installed by the manufacturer. Are there any good guides out there about how to properly measure a leaf spring or is it better to get it off and bring it down to a store like tractor supply and have them match it?