Can I swap the axle from over- to under-the-springs?

[adt2]

This seems like a pretty straightforward modification, but I don't want to do it and then have the trailer explode the first time I pull out of the driveway. I just bought an old, tilt trailer, and the frame is mounted on top of the springs. I'd like to remove the two U-bolts on each side and drop the frame so it's mounted under the springs, to lower the ride height a few inches. Any reason I can't or shouldn't do this? Anything to be aware of? Warnings, caveats, etc?

Thanks in advance for your help.

 

[UncleWillie]

Re: Can I swap the axle from over- to under-the-springs?

If by "frame" you mean the trailer's frame is on top of the spring, I can not picture how you could mount the frame Under the springs! ???

If by frame you mean the Axel tube, Mounting the Axel under the springs would raise the trailer.

Something got lost in translation! Maybe a picture would help.

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

You're right on all counts...I was in a hurry and posting from memory.

By "frame" I mean axle tube. The axle tube is currently under the springs; I want to move it over the springs, which, as you say, would lower the trailer. Here's a picture to help.

 

[T_Herrod]

Re: Can I swap the axle from over- to under-the-springs?

Is the axle arched? It appears not to be but it's hard to tell from your picture.

 

[UncleWillie]

Re: Can I swap the axle from over- to under-the-springs?

I though I had lost it!
So the real Title of the thread should be " Can I swap the axle from UNDER - to OVER -the springs?

Can be done.
One Issue. You will loose a couple of inches in suspension travel before the Axel strikes the frame.
Someone else will think of another.

EDIT: If you move it up, keep the top on top, do not flip the tube.
Your Caster, Camber, or Toe In, if any, would flip also.

 

[superbenk]

Re: Can I swap the axle from over- to under-the-springs?

Assuming you have the clearance for the axle above the springs at full compression it should be fine.

 

[Bob_VT]

Re: Can I swap the axle from over- to under-the-springs?

It is suggested that you obtain new axle bolts. They are not normal bolts and stretch when properly installed.

If you make the swap the stresses and weight will be riding on those bolts and plates...... you might even have an axle pin to locate into the springs.

Just a dumb question...... how much lower is it going to be???? Only a few inches at most. I would honestly leave well enough alone and get a step-ladder so you can work on things and not sacrifice ground clearance/suspension travel.

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

Is the axle arched? It appears not to be but it's hard to tell from your picture.

No, it's straight. And I have no idea why that picture is rotated...it was taken straight up and down and appears straight up and down on my computer. Weird.

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

It is suggested that you obtain new axle bolts. They are not normal bolts and stretch when properly installed.

If you make the swap the stresses and weight will be riding on those bolts and plates...... you might even have an axle pin to locate into the springs.

Just a dumb question...... how much lower is it going to be???? Only a few inches at most. I would honestly leave well enough alone and get a step-ladder so you can work on things and not sacrifice ground clearance/suspension travel.

Between lowering the frame and lowering the bunks, it'll be probably 6-8" lower. This is mainly for appearance and to make it a little easier to launch/retrieve the boat. When viewed from the side, the trailer just looks...wrong. There's a huge gap between the top of the wheel and the fender (maybe 8"?) and the whole setup just looks awkward. I'm guessing it was originally meant to be assembled the way I'm trying to do it, and somebody changed it to the way it is currently.

Next question: There's a small-diameter (maybe 1/4") bolt and nut on either end of the axle. It appears to be securing a little notched thing to the springs that rides on the axle tube. In the photo above, it's dead-center in the steel plate that the U-bolts go through. The head of the bolt does NOT come out the other side of the axle. Does this need to be removed during the procedure? Do I need to flip the notched thing to the opposite side of the axle? How do I get to the head? Seems like I'd have to remove the wheels and hubs to get at it.

 

[Bob_VT]

Re: Can I swap the axle from over- to under-the-springs?

Yup that's the locating pin for the springs and prevents side slippage of the springs and helps keep the axle aligned.

You also run the risk of destroying tires in less than 200 miles if your alignment is not right.

You said it is an old tilt trailer and that is why it rides high. Do you use the tilt to launch it or do you just back the boat/trailer in?

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

I haven't put a boat on it yet. Just bought the thing yesterday. The boat is still under construction.

 

[duke33]

Re: Can I swap the axle from over- to under-the-springs?

After looking at the pic again it does look like new u-bolts and plates.

 

[dlngr]

Re: Can I swap the axle from over- to under-the-springs?

I've changed both my trailers as you want to do-makes a world of difference launching at a shallow ramp. And,the lower center of gravity will make it a safer tow on the road. You will lower the trailer about 3 inches,from what I see,just make sure you have the clearance out back so your motor doesn't drag on the pavement.

 

[superbenk]

Re: Can I swap the axle from over- to under-the-springs?

As a fellow tilt trailer owner who doesn't use the tilt, I can sympathize with the desire to lower it even a couple inches. I've considered doing that to my trailer many times.

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

We are still recovering from the effects of last year's drought here in Texas...ALL the ramps are shallow.

I'm going to work on it some more this afternoon. Borrowed some jack stands from a buddy just a while ago so I can lift it up a bit. Still not sure how to handle the bolt/nut in the center of the square plate under the U-bolts...any direction there would be appreciated.

 

[tomdinwv]

Re: Can I swap the axle from over- to under-the-springs?

That's the center bolt fot the spring. Keeps springs lined up. You will either have to drill a hole in the axle tube for the center bolt to fit into or fashion a "spacer" out of steel plate to go between the axle and the spring. It is important that you measure, measure again and then measure again to make sure you get everything lined up right. There should be a spacer or a hole in the top of the axle tube to line up the other end of the center bolt. It's very important to get everything squared up and right or the trailer will not track right and/or eat tire like crazy. Good luck!

 

[tomdinwv]

Re: Can I swap the axle from over- to under-the-springs?

By the way, Like Bob from VT said, go get new u-bolts to mount the springs. Like he said, they stretch and should be replaced.

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

Okay, I am back on track now. There were spacers already in-place - notched steel deals that ride on the square axle tube and have a hole bored in the center for the bolt on the springs. All that was necessary was to unbolt the U-bolts, unbolt the springs, remove the springs and re-install them under the axle tube. I took the spacer deal that had been on top and moved it to the bottom; set it in the crook of the spring, centered the hole on the bolt in the spring, and then cinched the U-bolts tight to draw the axle tube into the notch on the spacers. Took a bit of fiddling to get the axle centered, but everything seems okay. I took it for a spin around the neighborhood and it seems to track straight and smooth.

Next project will be to replace the bunks and rollers, lights, and tires - which appear to be of two completely different sizes.

 

[superbenk]

Re: Can I swap the axle from over- to under-the-springs?

Someone earlier said you can't reuse those ubolts because they stretch when initially used. Did you get new hardware?

 

[adt2]

Re: Can I swap the axle from over- to under-the-springs?

No...just reused what was already there. The bolts looked to be in good shape and not nearly as old as the rest of the trailer.