Custom Enclosed Trailer Built Wrong

[TheKassman]

best example of reason of proper tongue weight you will ever see.

https://www.youtube.com/watch?v=w9Dgxe584Ss

[WAKY]

It shouldn’t be a big deal moving the axles unless there’re cutouts for tires. If it’s not right you will grow to hate it

[Ancabuild]

Originally Posted by palehorse89

Way Wrong, and not correct! If there is no tongue weight when it is empty, it won't tow without swaying all over.........10-15% HAS to be all the time for anything to tow properly........

Way wrong, the tongue weight is important when the trailer is loaded, if you have 500# in the tongue and 3000# on back of the axle you will be fishtailing anyway the tongue weight has to do with a loaded trailer 500# max in the tongue and the way distributed on axles and back so as to keep proper tongue weight and the rest carried by the capacity of the axles

[Loren B.]

Troy,

There is so much misinformation on this thread that I gave up reading it after the first page. I changed my mind and thought that I would try to explain some things. I have no intention of debating the rules of physics here so will not be getting into any discussions with people who are convinced that I am full of hooey.

First, tongue weight is not really the issue regarding trailer stability. It is merely a handy way to measure where the CG (Center of Gravity) of the trailer is relative to the axles. The farther forward the CG relative to the axles, the greater the tongue weight and the more stable the trailer will be while towing. For an example, look at where the axles are on a semi-trailer. The tongue weight on those trailers can easily be 50% of the total trailer weight. Have you ever seen a semi-trailer swaying back and forth behind a truck?

Second, while that video (a few posts back) is a great demonstration of trailer sway relative to where the CG is, the conclusion states that tongue weight should not be greater than 15% of the trailer weight. That is incorrect. As long as your hitch, your tow vehicle, and your trailer can handle the load, a larger tongue weight will always result in greater stability and less sway.

Third, as demonstrated in that video, a trailer that may be unstable when empty can be loaded in a manner that will result in a stable (no sway) towing operation. Also, a trailer that tows well when empty can be loaded with too much weight behind the axles, resulting in severe sway (instability).

Fourth, moving the load forward on the trailer will not result in a greater load on the front axle relative to the rear axle so long as the trailer itself remains level. If you tow with the tongue down (nose low) you will then transfer more weight to the forward axle which will result in less stability and more sway. The converse is also true if you tow with the nose up.

It's possible to have a two (or three) axle trailer that will have almost no tongue weight sitting unloaded, but that will still tow well when loaded properly. On your newly constructed trailer does the tongue weight increase dramatically as you start to lift the tongue? This is an indication that the forward axle is pretty close (fore and aft) to the CG and as you lift the tongue you transfer more weight to the rear axle. The tongue becomes heavier as you lift it. (Note: Obviously this does not apply to single axle trailers.)

If the tongue gets heavier quickly as you lift it, you may find that the trailer tows well when loaded, but it depends on how you load it. My CornPro flatbed trailer sits slightly nose down when disconnected. I can crank the tongue jack entirely off the ground and the trailer will not tip forward. But as soon as I level the trailer the tongue weight goes up and the trailer tows like a dream.

Fifth, an equalizing (weight-transfer) hitch will not correct for an unstable trailer load. Also, sway control devices may dampen the sway somewhat, but they do not actually correct for a poorly loaded trailer.

The bottom line is that without a greater understanding of trailer stability you won't really be able to tell how well it tows until you tow it, both loaded and empty.

Good luck.
-- Loren

[islandboy54]

I did not read everyone’s comments above, but it is not hard to relocate axles rearward a few inches to get you enough tongue weight empty. They need to correct it, period. You do not want a light trailer tongue. And they actually tried to blame it on torsion axles? Well, BS. I have built trailers and towed the same for decades.

[palehorse89]

Originally Posted by Ancabuild

Way wrong, the tongue weight is important when the trailer is loaded, if you have 500# in the tongue and 3000# on back of the axle you will be fishtailing anyway the tongue weight has to do with a loaded trailer 500# max in the tongue and the way distributed on axles and back so as to keep proper tongue weight and the rest carried by the capacity of the axles

Tongue weight is just as important when empty just as it is when loaded......with only 50# of tongue weight when empty, this trailer will not tow right........it will be just like moving the 4 wheeler to the rear of the trailer in the video......
These enclosed car trailer's have a lot more than 500# tongue weight........Mine is rated at 1500#.

[BlueNomad]

Reading all these new comments, I am agreeing with a lot of what is said.

Here is something I learned about this build. When the tongue was tilting down towards the ground, the front axle tires were under inflated and the rear axles were at proper psi. When the front tires were inflated to the same as the rear, the tongue was level. From that point, if you lifted the tongue the weight of it went up as you started to off load the weight on the front axle. To me, that is a bad design. If you lowered the rear tire pressure, the tongue would go up.

Again, if that is right, it seems wrong. If the trailer would to lose pressure in the rear tires on the road, it will start to lift up the rear of the truck, or at least off load it to some point.

Of course this is based off an unloaded trailer and loading the trailer right, is up to me. But again, I should not have to load up a trailer with enough bias toward the front to offset the current bias and the added load bias.

As for moving the axles, the mounts are welded to the chassis and cutting those off and moving them is easy enough. And for a trailer that the wheels are outside of the box/frame, it would only be moving the fenders. Pretty easy. But this trailer is 101" wide and the trailer has all been welded around the wheel location. The steel floor and cross members, the walls all are boxed off and welded to form around the axles. To move the axles back even a few inches, you are ripping out a huge amount. The manufacture at least admitted that it would be cheaper for them in both time and cost, to just start over.

I have talked to an attorney, and confirmed they are in breach of contract and to the point of committing Theft by Contract. But I am still hoping that they the manufacture makes good and fixes this problem.

Thank you all for your input.

[KanzKran]

Originally Posted by BlueNomad

Here is something I learned about this build. When the tongue was tilting down towards the ground, the front axle tires were under inflated and the rear axles were at proper psi. When the front tires were inflated to the same as the rear, the tongue was level. From that point, if you lifted the tongue the weight of it went up as you started to off load the weight on the front axle. To me, that is a bad design. If you lowered the rear tire pressure, the tongue would go up.

Again, if that is right, it seems wrong. If the trailer would to lose pressure in the rear tires on the road, it will start to lift up the rear of the truck, or at least off load it to some point.

Of course this is based off an unloaded trailer and loading the trailer right, is up to me. But again, I should not have to load up a trailer with enough bias toward the front to offset the current bias and the added load bias.

That is the nature of independent suspension systems like that. Equalized leaf spring systems will, as the name suggests, equalize the load between the axles independent of the frame angle to the ground (zero being parallel). You can jack the tongue up and down and the jack load doesn't change in any meaningful way.

So yes, a squishy tire that's riding a bit low will lose a little load and the other will have to pick it up, which is just one more reason to maintain tire pressure. Same thing happens when going over a speed bump - as each wheel rides up the bump, it takes more load and the other(s) unload, while equalized leaf springs just sort of walk over the bump, at least at low speeds. High speeds complicate things, as they always do.

[LETMGROW]

I am sorry to hear about all the problems you are encountering while trying to get your trailer built. If it was me I would get out of the contract and move on to a different custom builder.
At this point in time there is no doubt the builder is not your best friend. Allowing them to alter the placement of the axles now that they are already in place could result in slip shod workmanship. They are going to hurry to get this build finished and out the door. Even if the builder started from scratch they might just throw the trailer together just to get rid of you.
I'd pursue getting my deposit returned and move on to a different builder.
If you did accept the trailer from them regardless of what they do would you ever be comfortable with the trailer?
Lynn

[BlueNomad]

Originally Posted by KanzKran

That is the nature of independent suspension systems like that. Equalized leaf spring systems will, as the name suggests, equalize the load between the axles independent of the frame angle to the ground (zero being parallel). You can jack the tongue up and down and the jack load doesn't change in any meaningful way.

So yes, a squishy tire that's riding a bit low will lose a little load and the other will have to pick it up, which is just one more reason to maintain tire pressure. Same thing happens when going over a speed bump - as each wheel rides up the bump, it takes more load and the other(s) unload, while equalized leaf springs just sort of walk over the bump, at least at low speeds. High speeds complicate things, as they always do.

If the axles where in the right spot and the CG was in front of the front axle, if the rear tires loose psi or were even removed, the front axle would take the load, but the trailer would still want to fall forward. Independent or equalized leaf should act the same way, right? If you set the center hanger of the leaf axles back to a 60/40 or 1" inch for every foot of deck length, behind the center, you would still have the same reaction?

[LarryinID]

Originally Posted by BlueNomad

Thanks all for your input.

I went back to the factory to try and explain the issue with the weight. Owner wasn't there and the 2nd in command continued to insist he is right. "we design our trailers to be lifted by hand so you can move them"

So I tried to present my case on why you need weight on the tongue. On to deaf ears. So I will try again with the owner after he is done being sick.

Here is a drawing of their layout vs where the axles should be. Along with a weight calculation on their configuration.

The simple reason you need the tounge weight is to prevent the trailer from oscillating and flipping. Sometimes you may want to tow empty. The guy is ignorant.

[KanzKran]

Originally Posted by BlueNomad

If the axles where in the right spot and the CG was in front of the front axle, if the rear tires loose psi or were even removed, the front axle would take the load, but the trailer would still want to fall forward. Independent or equalized leaf should act the same way, right? If you set the center hanger of the leaf axles back to a 60/40 or 1" inch for every foot of deck length, behind the center, you would still have the same reaction?

If you lose air in the rear, the wheel will sit lower, but it'll still take the same load. That's the equalization part. And the tongue weight doesn't change with coupler height, assuming the CG is down at the deck. But yes, if the trailer CG is forward of the center point between the two axles, it will try to fall forward, but unlike independent suspension systems, the front axle won't take additional load until it runs out of travel in the rockers or the axle hits the stop. That's why it's important to tow trailers with torsion suspension systems level (always a good idea anyway). If the CG is forward of the front axle of an independent 2-axle suspension system trailer, it'll just tilt over onto the coupler with the front axle as the fulcrum and the back wheels coming off the ground (empty, lightweight trailer assumed here).

Just imagine the suspension is infinitely stiff - essentially no suspension, just axles bolted right to the frame. Lift the tongue above level, and all the wheel load is on the rear wheels and the tongue weight goes high. Let it fall forward, and it's all on the front wheels and the tongue weight is low, or zero if the CG is right on top of the front axle, or negative if it's behind it. The suspension just adds a little softness; very little when it's empty and light. Loren B. had gave a very nice explanation above.

[wellsit]

I'd stand firm with them. You won't be able to tow safely with all that weight behind the axles. You need a forward weight bias to keep sway in check. Too much weight aft of axles and you'll be prone to dangerous trailer sway at highway speeds.

[Itchytoe]

Let me preface this post by saying that I'm assuming that the OP is building a travel trailer (kinda like what the tiny house people do) out of this trailer. That's how I read the original post so that's what I'm going with unless the OP corrects that assumption.

Loren from a few posts above is giving some good advice, but I feel as though it's only half of the story. It's definitely true that loaded weights matter and how you can load a trailer to in a way that makes it tow well or poorly. You can also adjust the load in order to correct any issues. We can fill our water tanks and propane bottles to adjust the weight distribution. Adding a couple of propane bottles and batteries where they normally are in a travel trailer might give this empty frame the perfect weight distribution. 200 pounds extra on the front tongue can make a big difference in a 3500 pound trailer.

That being said, once this trailer is built out, a couple of propane bottles and batteries won't be anywhere near enough weight to move the center of gravity enough to get 10% tongue weight again. 200 extra pounds on the front tongue is nothing on a 10,000 pound trailer.

Travel trailers have a pretty even weight distribution across the frame in most cases. This trailer is a custom trailer being built for that purpose. It should have weight ratios that reflect it's intended purpose, an evenly distributed load. Such a trailer would have the ideal tongue weight (or a little more actually) when unloaded. In order to "load" the trailer to get the required tongue weight (center of gravity placement), it would have to be built with a front kitchen and bath with as little weight in the rear as possible. The standard front bedroom center kitchen won't work here. A rear bedroom/front kitchen and bath design just might work on this frame, but that's not the kind of trailer this is going to be. This one has a drop down rear door. That's a toy hauler. Toy haulers have notoriously high tongue weights when empty because the toy is loaded in the rear and is a counterbalance. There's no way get enough weight in the front of this thing to work as a toy hauler unless you just put 3,000 pounds of bolts up against the front wall and have a very light toy to load into it. Even then, it'll be over it's weight ratings by a large margin once you add in the rest of the rig.