Ramp Door capacity

[Blue Mule]

I have a new 8.5x24' enclosed trailer. Lark United Manufacturing is the brand. GVWR is 9,990. Twin 5,200 lb. axles. It was advertised as a "car hauler".

I cannot locate the weight capacity of the rear ramp door anywhere. One would assume that the ramp door would support at minimum the same weight as the payload rating of the trailer but I need confirmation of this. I loaded my Workmaster 40 into the trailer and the ramp door started making horrible noise. Popping and cracking like a bowl of Rice Crispies. The tractor has a listed weight of around 3,000 lbs. Loader is what, 900 more lbs? 400 or so more for the box blade? So 4,300 lbs. total weight, which is WELL within the payload capacity of the trailer. But the ramp door sounds like it's about to snap in half (although it doesn't, and there is no visible bowing or damage to it).

Anybody know what these typical box trailers can handle at the rear doors?

 

[timswi]

Can't answer specifically but half the car will generally be on the ramp at any given time. Tractors etc are probably placing their full weight on the ramp. A theory anyway.

 

[4570Man]

They’re not very beefy. I’ve never been brave enough to try anything besides a lawnmower in mine.

 

[CH4Ohio]

I think I'd lay 2"x10" boards down to match the tire tracks if I was trying to load a car or tractor. Same as above, I've never loaded anything heavier than a lawn mower in mine. But I've had this same concern and often wondered how that gate, made of plywood and thin metal skin, would stand up to a heavy vehicle.

 

[Midniteoyl]

I've seen skid-steers go up them at least once on theft videos

 

[War Eagle 2]

I can only tell you about my experience. I had a custom built Diamond enclosed trailer. It was 7 x 16 and the rear door opening was made with 84" clearance on the height. It had 2 5200# torsion axles and a ramp door. I had all the wall, ceiling and floor supports spec'd at 16"o.c. rather than at the standard 24"o.c. build. I had to have the ramp beefed up to handle 4500#. They told me the standard was 1500#, an upgrade was 2500#. Now this just may be how Diamond handles things. But I think I would be very cautious about making assumptions on what a ramp can handle based on total trailer weight capacity.

 

[Blue Mule]

Hmmm.. Well that would be pretty useless then, wouldn't it? A car hauler rated to carry 6,500 lbs. but only able to support 1,500 lbs. at the ramp door.

My first question to the manufacturer would be, how the h*** am I supposed to get the car IN the trailer?

I've been trying to contact Lark Manufacturing for specifics, but of course, like most south Georgia trailer sweatshops, they aren't responding.

 

[4570Man]

Hmmm.. Well that would be pretty useless then, wouldn't it? A car hauler rated to carry 6,500 lbs. but only able to support 1,500 lbs. at the ramp door.

My first question to the manufacturer would be, how the h*** am I supposed to get the car IN the trailer?

I've been trying to contact Lark Manufacturing for specifics, but of course, like most south Georgia trailer sweatshops, they aren't responding.

It’s probably 1500 pounds per axel which would load some cars. If it was upgraded to 2500 pounds per axel you could load most cars. Bottom line is light duty covered trailers aren’t meant to haul equipment.

 

[sea2summit]

I've seen skid-steers go up them at least once on theft videos

Saw the same video I think....trailer didn't end up making it very far.

I wouldn't want to make a habit of driving a tractor up and down one of those...heck I wouldn't make a habit of driving a car in and out. I think it's more of a way to identify the style of trailer than it is a description of actual purpose.

 

[4570Man]

Saw the same video I think....trailer didn't end up making it very far.

I wouldn't want to make a habit of driving a tractor up and down one of those...heck I wouldn't make a habit of driving a car in and out. I think it's more of a way to identify the style of trailer than it is a description of actual purpose.

A car couldn’t clear the sides by much. Getting out must be fun if not impossible.

 

[Blue Mule]

So I finally got somebody from Lark to call me back. Load rating is 4,500 lbs. at the ramp door.

I saw online at another brand of the south Georgia sweatshop trailers that theirs are listed at 4,500 "static" load and 5,500 "rolling" load.

That makes a LOT more sense!

So my 4,300 lb. tractor will be OK. I've been laying additional plywood down on the ramp when I load it anyhow, so it'll be fine.

 

[Midniteoyl]

I've been laying additional plywood down on the ramp when I load it anyhow,

Was gonna suggest maybe reinforcing the door anyways. You could also attach a swinging brace to the outside that would swing down and provide additional support midway up the ramp. Does the door have the metal traction 'ramps' embedded?

 

[LD1]

Most of what you see in them enclose car haulers are people hauling racing equipment. Cars built for racing usually dont weigh much....but having a 9k trailer allows for hauling more than just the car. Tools, a golfcart/atv, spare parts, etc.

Dont EVER assume that a ramp is rated for trailer capacity.

How many 7k landscape trailers out there that weigh 2k empty (5k payload) would you trust driving a 5k tractor over the light weight mesh end gate?

And have seen several dump trailers, 14k rated, that have a sticker on the door that says "max ramp load" and its less than capacity of the trailer.

Its all about weight distribution. Even with a boxblade on....you are probably still heavier on the front axle with the loader on. that on top of either ags or R4 tires where the cleats put one heck of a point load on some thin plywood certainly could explain the creaking you have heard.

 

[Blue Mule]

Was gonna suggest maybe reinforcing the door anyways. You could also attach a swinging brace to the outside that would swing down and provide additional support midway up the ramp. Does the door have the metal traction 'ramps' embedded?

Hard to say without unscrewing some of the exterior sheet metal to look inside, but it appears to be 1.5" to 2.0" steel tubing framework, with 3/4" plywood sheeting screwed to that framework. It's a very heavy door, and without the spring loaded cable assist it would be a chore for a grown man to lift the door and close it. But no, the driving surface itself is simply the 3/4" plywood sheeting.

 

[gtbensley]

I tried to figure out my doors weight rating as well and could never come up with a number. I have no doubt its probably not rated for what the trailer is rated to haul though.

 

[scaredychicken]

there are always solutions to make the applications work, but I agree with Blue Mule ... the Ramp-Door should be able to (at a minimum) support the weight of legitimate cargo ... cars, tractors, whatever. It seems silly that you would need to reinforce the ramp simply to load / unload.

 

[Slowpoke Slim]

Back in my drag racing days I ran into this a lot. Most guys that bought an enclosed "car trailer" just assumed the door would support the weight of about any car. The standard door will not. At least NOT FOR LONG. When I had mine, I ordered it with an optional heavier door, hinges and tensioners. On enclosed car trailers it's almost always the rear door that goes out in them. Too many flimsy ones out there. If you didn't specifically order it with upgraded door and hardware, then you got the cheapest they could get away with. When you come back to them 2 years later with a broken door, they will just tell you that it's your fault for overloading it. I ran into guys all the time on the drag circuit that had this exact thing happen to them. That door is "rated" (if you can call it that) to have ONE axle of a car on it at a time. And not a very heavy car either.

It may not explode and burst into flames the FIRST time you load a heavy car (or tractor in your case), but that doesn't mean it will take it for long. That horrible sound you're hearing is the door breaking. The frame of the door (if it has one) is cracking, as are the layers of wood. As you flex that door, it's pulling itself apart a little more each time. I would strongly encourage you to put some kind of serious bracing on the inside wall of the door. Like mount a couple of 2x8's or 2x10's along the tire track path. It would also be a good idea to rig up some kind of wood support (think like miniature wooden saw horses) for the underside of the door when it's folded down for loading.

It's only a matter of time before you break that door if you don't do something different.

My 2 cents anyway.

 

[crazyal]

Back when I was racing I had a 26' enclosed Haulmark trailer. You could tell the door was heavy by how much tension was on the cables going to the springs. Well I bent it loading a 3000# car. So I rebuilt it. It's actually very easy to do. The rectangle tubing was very thin wall (I think it was .065" wall 1" x 1 1/2"). Needless to say you can't find stuff that thin at most steel yards. In fact 1/8" was the thinnest I could get.

The hardest part was taking the tension off of the spring. Then I just unscrewed the aluminum and plywood and used a 4 1/2" grinder to cut the welds. The top and bottom pieces of steel don't get stressed so I just replaced one piece of steel at a time so the over all squareness and dimensions didn't change. I swapped them all out. I didn't but I had thought about adding an extra piece or two to make it even stronger. But the taillights were recessed into the door so I would of had to relocate them (which would of meant replacing the aluminum sheet metal) or worked around them. I didn't feel it was worth the effort. I didn't even need to replace the spring for the door.

I'm sure someone here could tell you how much weight a 1" x 1 1/2" x .125" rectangle tube will support. I think it was 6 1/2' long. If you own a welder (a mig would be much better since the top and bottom metal could be very thin) then I would beef it up if I was worried. If using the trailer for a tractor you could even add extra supports to align with your tractor's tires.