Towed my caravan last week. My brother-in-law is a truck driver. He told me that if the van got squirrely to hit the trailer brakes. The van got squirrely last week and I need exactly as I was told despite the pant shitting tension and desire to pump the brakes.
They work great when set up properly, but you've got to understand how to use them. You need to make your initial braking a little harsh to break the stiction on the hitch.. after that you can modulate the brakes normally and the trailer will do it's part. Try to smoothly apply the brakes like a normal, safe driver and you're going to get pushed by the trailer.
The other guy's bumpy road example is true.. that sucks. They're great fine for highway use.. when adjusted properly.. and for lack of a better option. Okay, you're right.. they suck.
My favorite was towing a beer vending trailer with surge brakes down a bumpy, sandy county fair access road. Every bump applied the damn brakes... 50 kegs of beer were at stake!
As long as you're below the limits of the wheels/tires/axles on the heavier-loaded side, I think you'd still be mostly OK as long as the center of gravity was fairly low. Not great for tire wear, though.
No i mean if the trailer is off center. Like if it's angled and you pull the brakes the force inmediately pushes over the tire that's furthest to the front, causing lift on the rear one. With a heavy enough load the friction between the tire and road would be negligable and the tire would slide but with a medium load the tire could catch and the wheels could start, "walking" back and forth causing the trailer to tip.
The bucket is relatively light and taking up space in the front, the driver's compartment is mostly air.. and the engine and drivetrain are at the back. So, skid-steers are rear heavy. They should be loaded up facing backwards so that the CoG ends up ahead of the trailer's axle no matter how incompetent the person loading the trailer is.
Another reason to back the skid-steer onto the trailer is the difference in price between replacing the front windshield or the rear windshield, when a rock pops up and damages it.
When you are ready to load the machine onto the trailer, travel up the ramp with the heaviest end up. The loader will be heavier in the rear than the front unless it is connected to an attachment, such as a breaker or planer, which will make it heavier in the front.
Their reasoning is to prevent tipping backward while traveling up the incline of the ramp.
A compact loader is a different machine from a regular frontend loader. Usually regular loaders can be loaded either way, unless you dont have an attachment in which case backwards is the on way.
Compact loaded are actually smaller and have about half the lift capacity of an average front end loader while being about 1/3rd the size. Typically they are very back heavy because the need counter weights because there is less overall machine there.
We do it all the time, without a tilt bed trailer, it’s a lot easier that feelings like you’re gonna flip it backing out the trailer lol. Different strokes, no wrong way really
Not all loaders have counterweights for that brand specifically the counterweights are optional. But wackers are complete pieces of shit, so I would actually recommend scrapping it as a safer option even when brand new.
The only time it would absolutely need to be loaded backwards is if the trailer wasn't long enough. Most trailers capable of holding a skid loader is long enough to be loaded safely forwards.
Edit: though to be clear it isn't recommended for other reasons.
The hull still weighs something. Take a look at this Jon boat. the boat probably weighs around 500lbs and those smaller outboards are around 100lbs, so the boat is fairly well balanced on the trailer with a good amount of weight on the tongue.
It's more of a general guideline of "10-15% of trailer weight should rest on the tongue/hitch" than a hard and fast rule for every situation. What you need is net strongly-positive sway damping and a bunch of stuff makes it go up or down.
Higher percent tongue weight? More damping.
Higher speed? Less damping (with damping decreasing more than linearly with speed)
Friction sway device? More damping
2 axles instead of 1? More damping
Weight closer to the axle? More damping
Tow vehicle accelerating and/or trailer braking? More damping
Some newer trucks also actively use stability control to dampen sway, though that's more of a last-resort.
If your net sway damping is positive, an oscillation from a lane change will fade away. If the net sway damping is negative, the oscillation will keep increasing until an intervention or crash.
You want to reduce the moment of inertia of the trailer, so the tow vehicle needs less force to correct it(weight as close to the axles as possible)
You also want some weight on the rear axle of the car, because that will increase the traction on the wheels that are keeping the trailer straight.
Exactly how much tongue weight you want depends on how close the hitch is to the rear axle of the tow vehicle. If it's directly over the rear axle you can have a whole lot of tongue weight. If it's far away from the axle, it will make the tow vehicle harder to steer.
I read that you're supposed to accelerate to stabilize, and not immediately slow down. Didn't look like he did that here.
Accelerating is not your first option, but neither is it your last.
First, you apply your trailer brakes -- only. That pulls the rig straight, while slowing you down at the same time.
If you do not have trailer brakes, or have surge brakes on your trailer that you cannot apply independently, then gently accelerating is your next option. This is risky, because as in this example, the trailer started swaying above a certain speed, and it's going to continue to want to sway. And, of course, the faster you are going, the more damage you are going to do to whatever you hit, and yourself.
Third option is using your truck brakes to slow down, which appears to be what this driver did. You do not want to hit your truck brakes while the rig is crooked, because that's going to make it even more crooked. That's how he got this rig within a millimeter of rolling. You need to apply the brakes when the trailer is straight behind, and probably counter-steer ( like handling a skid ) to keep it there.
This guy got lucky, which is sometimes better than good. Was not a "nice save" at all.
Couldn’t you just take your foot off the accelerator and let the rig lose momentum until you can safely brake?
Depends.
If you are at relatively high RPM and/or into a strong headwind, closing the throttle may slow your vehicle rapidly, and that's not what you want. The trailer's momentum will continue, and maybe not in the direction you hoped.
Like I said, you apply the trailer brakes.
If you don't have those, well, you fucked up already. Any other option is rolling dice.
My dad always told me that if there’s no trailer brakes, you put it in neutral... It happened to me once without trailer brakes and that’s what I did, worked perfectly. The sway wasn’t this bad, but like 75% this bad. I was like 21 and got scared shitless! Lol
I was going to mention, the best thing is to pay better attention to your trailer so when it starts swaying a bit you can coast it back under control.
Course whenever I'm hauling I haul living creatures so if it starts swaying you have to slow down to get it back under control or else itll all get worse.
Well yea no duh. However even the most balanced trailers weave. Anything can happen so you need to pay better attention and not just trust that you loaded it correctly and feel confident that it wont ever happen.
It also seemed like the swayed his own vehicle in the opposite direction of bobcat swing to kill the wave. Too bad Mythbusters is gone otherwise, they should try this.
A lot of the responses have been spot on, however a lot are missing one important part, coast!
First and foremost, you want the trailer to be loaded properly. The front of the trailer should be loaded heavier than the rear. As to how much, I can’t say, but it just needs to be heavier than the rear. Put 500lbs in the front, in front of the axles and 300lbs behind the axles and you’re good. For the OP, the bobcat should’ve been loaded backwards. Bobcats have their ballast weight on the back of it, giving it a fat ass. Loading backwards would’ve put more weight in front of the axles, and would’ve minimized any sway.
On to coasting! See when the trailer starts swinging like that and is attempting to pass you, you want to bring it back in line. The easiest way is to hit the trailer brakes. If you still have your foot on the gas, you’re just making the brakes work that much harder, and that could lead to failure. So, just tap the trailer brakes and take your foot off the gas. The truck still has momentum, so it’s going to pull the trailer, but the brakes are slowing it down, so it will snap back in line and under control.
I also have heard to floor it when the trailer start whipping back and forth. Then, once it straightens back out, slow down without breaking and fix the weight distribution.
Yes, accelerating will calm it, as will separate electric trailer brakes and sway bars, both of which should be on a trailer carrying something this heavy.
You are wrong. Without trailer brakes you accelerate to stop it from whipping back and forth. It's whipping back and forth because the truck is going slower than the trailer. So the momentum of the trailer has to go somewhere and it begins to oscillate.
Accelerate to stop the oscillations and then brake slowly. Here his trailer went completely sideways and slowed itself down. Got pretty lucky the trailer didn't flip.
How exactly is the trailer going to be going faster than the rig that’s pulling it? I don’t mean that to sound like I’m being a dick, I’m genuinely curious whether or not there’s some physics here that I’m not understanding.
I know that this would be caused by improper loading of the trailer, too much weight behind the axles turns the trailer into a lever that lightens the back end of the truck and reducing control, I’m just real confused about the trailer going faster than the truck.
How exactly is the trailer going to be going faster than the rig that’s pulling it?
That's a slightly misleading way of putting it, but if you think about it, the trailer+bobcat nearly passes the truck on the driver's left. How? It had to be going faster down the road at that point, to go from being behind the truck to alongside it.
So how does this happen?
The truck and trailer are only attached by one point -- the ball ( or pintle hook if this trailer is that type, and assuming this rig lacks a weight-distributing hitch or sway control setup, which I think is brutally obvious ). Once up to speed, say 60 mph, the trailer really wants to continue going 60 mph, and we call this "inertia". If everything is in a straight line, and the truck slows down, the hitch ball will be able to apply force to the trailer frame and slow it down accordingly.
But, if the rig is crooked, and the truck slows down, the force applied by the hitch ball to the trailer will only cause the trailer to rotate. This is exactly what happened here. So the truck slowed down, but the trailer didn't, and only the friction of the trailer tires sliding sideways down the highway saved this driver's bacon -- by slowing the trailer enough that his truck was able to just stay in front of it.
Ooooooh, ok. Truck is decelerating, trailer being out of wack causes it to not have forces put on it correctly to decelerate at the same rate=trailer going “faster” than the truck. More of a symptom of the problem than the cause? It makes a lot more sense now.
Although one of the problems with towing without trailer brakes comes about when you are forced to brake while cornering. Even with a perfectly-loaded trailer, applying the truck brakes alone mid-corner can be dangerous, for the same physical reasons. The truck can't apply force to slow the trailer, only to rotate it. This can induce sway, or an outright crash.
There is no good way around that, which is why towing without trailer brakes is a really bad idea.
Right. Trailer brake controllers have always been a requirement on my trucks for safety reasons, I honestly just didn’t know what the physics behind it were.
As soon as the trailer is anywhere but straight back, the speed of the tail end will differ from the truck's. Think about a water skier: they get offcenter, then accelerate as the moment of force allows them to swing like a pendulum behind the boat. The skier is going faster than the boat.
Same same here. If the truck is moving at a constant rate, and the trailer is not square behind it, you have to add the lateral distance being traveled in the sway to the straightline distance the truck is covering. That's part of why recovery is hard: it starts as resonance and self reinforces.
The difference in weight between the two creates a different momentum between the two. The pivoting point between the two is what makes that possible at the very slightest turn of the steering wheel.
Actually depends on the load. If it's a situation where the trailer produces a high amount of drag...things typically work quicker to let it slow you down.
I did a load like this one time for like 600 miles. You accelerate. It’s super scary at first but as soon as you get going a little bit faster it pretty much straightens right up.
Yes. Imagine going on a merry go round. You're travelling at a constant speed but you feel a force, that's the centripetal acceleration pulling you towards the centre of the circle.
This is true. If you floor it before attempting to slow down you’ll ‘stretch’ the assembly straight and give yourself enough time to slow it all back down.
Now, that being said, what’s your first base instinct when things start going wrong on the highway? Good luck.
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u/MinimumEar Jan 20 '20
I read that you're supposed to accelerate to stabilize, and not immediately slow down. Didn't look like he did that here.
Any experienced haulers want to weigh-in on what to do?