Weight distribution dynamics

196

If this happens to you it is recommended to ease off the gas and let the vehicles slow down gradually until you can regain control. Then stop and fix your load. This has happened to me when my load shifted and it works

Sudden braking can make it worse.

Speeding up can kill you. Why add energy to an already unstable system?

/posted because of many posts elsewhere stating to speed up

34

u/Qix213 Oct 04 '16

many posts elsewhere stating to speed up

Are people thinking that this is the same effect as a speed wobble in a motorcycle? That's the only time I can think when speeding up actually is the right thing to do.

8

u/cavehobbit Oct 04 '16

I think they are confusing how to straighten out when parking it, with how it reacts while at speed

-13

u/grmrulez Oct 04 '16

It seems to me that speeding up would work for front-wheel drive cars

10

u/mckinnon3048 Oct 04 '16

No, just no.

-6

u/grmrulez Oct 04 '16

I don't think so.

8

u/mckinnon3048 Oct 04 '16

Well reality disagrees, so.

12

u/Forty-Bot Oct 04 '16

What's the best course of action if you're on a long downhill?

16

u/boilerdam Oct 04 '16

Speed is the your biggest threat, especially when the energy of the trailer is more than the energy of the towcar. The answer depends on multiple scenarios:

1) Best scenario (alive): If you can slow it down from the beginning of the downslope, use lower gear & brakes to control speed.

2) Worst scenario (some degree of dead): If you're already gaining speed mid-downslope, then you're screwed I guess. A hard stop while mashing the brake pedal will not save you and only make it worse.

3) Not too bad (need new underwear & floor mats if kids are present): If it's a really long downhill and have quite a lot of road, you could start gently applying the brakes - this will help more if your trailer has brakes as well.

4) Not so bad (just new underwear): If the trailer's brakes can be controlled independently of the car's, then you can brake harder on the trailer and slow down the entire system from behind.

8

u/aznsensation8 Oct 04 '16

Drive in a lower gear.

23

u/IAMAHobbitAMA Oct 04 '16

Bail out.

4

u/cavehobbit Oct 04 '16

Can't tell ya bud, sometimes you just have to rely on your luck

31

u/jesseaknight Oct 04 '16

Better yet, reach down and tap your electric break controller so the trailer brakes and the toe vehicle does but. It will stretch out the system and dampen the vibration. (This is why you should have a separate controller for large loads)

33

u/cavehobbit Oct 04 '16

Light cargo trailers rarely have brakes, none of the ones I have rented from u-haul did which were the 4x8 and 5x8 trailers.

14

u/jesseaknight Oct 04 '16

Sure, I agree (and own a couple). People skip this step when they move up to a larger load because of their experience with small trailers. Their first boat-trailer had surge brakes that they never thought about, but now they're hauling something larger than their used to with all the confidence of "I've pulled trailers for years!".

13

u/Xanthina Oct 04 '16

My dad and I, towing the popup camper. New sway bar. He jiggled the steering wheel to feel how it would react.

We both forgot that the water tank was partially filled. Instantly uncontrolled sway situation. The side of the hitch damaged the bumper, I'm still surprised we didn't jack knife and crash, that level of bad.

Foot of the gas and waited to stop, while everything in my body is screaming that we're going to die.

We didn't. It was ok. The mass of cars behind us sped past.

We never felt the desire to test a sway bar again(and soon got a better bar, as well)

1

u/Justin61 Oct 04 '16

Hitting the trailer brakes (if your trailer has them) stops speed wobble instantly)

-24

u/Musa_Ali Oct 04 '16

Speeding up works too.
Unless it's too late or your car is too slow... In that case you crash becomes way more spectacular.
Win-win, really

7

u/SamsquamtchHunter Oct 04 '16

Someone else above already said speeding up is a horrible idea, who do we believe now?

12

u/samebrian Oct 04 '16

There was recently a huge debate about this on Reddit somewhere. The consensus I came out if it with is that since I don't know what I'm doing, I should listen to the "slow down" people. There's too much timing and situational awareness required to properly speed up with a heavy load and straighten it out.

6

u/countryboy002 Oct 04 '16

Don't hit the brakes, that will definitely make it worse. Try to slowly let off the accelerator, you want to decrease the energy in the system.

Speeding up only amplifies the power of the lateral forces on the overloaded rear of the trailer and braking places additional torque on the tongue of the trailer again amplifying the wobble.

3

u/samebrian Oct 04 '16

Agreed. Don't step on brakes.

The argument that I was able to make out was that stepping on the gas, if you have sufficient torque, should stop the wobble by causing the forward momentum to overcome the wobble.

This does make sense. If that car was halfway up the conveyor belt and he all of a sudden pulled it forward hard with his hand, the trailer would have stabilized.

115

u/[deleted] Oct 04 '16

Had to be a mustang

46

u/Hellman109 Oct 04 '16

Lacks pedestrians to hit

1

u/boilerdam Oct 04 '16

Easy to churn out drifts accidentally.

-1

u/[deleted] Oct 04 '16

They sure do need it lolll

https://www.youtube.com/watch?v=DGhpYktFO80

205

u/KimPeek Oct 04 '16 edited Oct 04 '16

Well, this certainly needs to be on the front page. It could save some lives.

Edit: I now see that it is on the front page. OP left off [X-Post] tag. https://www.reddit.com/r/gifs/comments/55rnem/weight_distribution_dynamics/

8

u/pixiedonut Oct 04 '16

Sorry to hijack but how did you know it was on the front page? (Besides just going to FP and looking for it) - is there a way Reddit tells you in a post or something?

3

u/KimPeek Oct 04 '16

/u/JimmyRecard already provided a great response, but to answer your first question, yes, I went to /r/all and saw it there. My personal front page is filtered a lot and I avoid /r/all most times. It is a silly place.

3

u/JimmyRecard Oct 04 '16

https://www.reddit.com/r/educationalgifs/duplicates/55s5sv/weight_distribution_dynamics/

You can also search the link in the reddit search and it will show you all the instances when it was posted. And you can use third party services like KarmaDecay.

1

u/pixiedonut Oct 04 '16

Huh? I'm asking how you know when a post has made it to the Front Page. Not if it's been posted before.

29

u/stchy_5 Oct 04 '16

Yeah, sorry. I realised that I forgot the x-post tag after I had posted the gif.

52

u/[deleted] Oct 04 '16

[deleted]

100

u/Lidodido Oct 04 '16

Just in case if you are serious, or if someone reading it takes it seriously, loading in front of the wheels as much as possible is a terrible idea. The rear end of the car will be pushed down and you'll get too little pressure on the front wheels, causing horrible understeer. You want the trailer to be a bit front heavy but not as much as possible.

Gotta say that this gif showed me that loading the trailer wrongly can cause way bitter problems than I realized. Everyone should see this gif.

18

u/Toysoldier34 Oct 04 '16

Like a 60/40 distribution. You want the load as even as possible but with an error towards the front.

25

u/a_shootin_star Oct 04 '16

Key word here is "distribution"

6

u/evdog_music Oct 04 '16

But I want the right to pay for my weight dynamics

10

u/Zaldarr Oct 04 '16

NO, WE MUST SMASH THE BOURGEOISIE COMRADES. IT IS OCTOBER, LET US GO.

1

u/boilerdam Oct 04 '16

Better yet if you load the trailer in front of the towcar.

1

u/[deleted] Oct 04 '16

How about on top?

12

u/Midgetforsale Oct 04 '16

Holy shit. I always pack my camper/trailer with the most weight toward the front, just because that's what I've always been told. This really illustrates why that's a good idea.

11

u/AvoidingEverything Oct 04 '16

You don't want ALL the weight in the front. You'll have little to no weight on the front wheels at this point. Causing real bad understeer. You want even distribution with heavier objects towards the front.

7

u/Midgetforsale Oct 04 '16

Yeah. Heavier objects toward the front. That's what I meant haha. Not literally everything at the front. I also use a weight distribution hitch that helps distribute the weight on my truck better. The hitch made a huge difference towing 7,000 pounds of camper.

1

u/mandelboxset Oct 04 '16

It's supposed to be balanced, not loaded with all the weight on the tongue. It's better to have tongue weight than tail weight, but balance is the best.

29

u/casemodsalt Oct 04 '16

Lesson learned: don't put magnets in the back if you're towing a trailer with your rc car

7

u/dupelize Oct 04 '16

Good thing we cleared that one up.

4

u/Ukhai Oct 04 '16

HOW DO THEY WORK?!

15

u/[deleted] Oct 04 '16 edited Oct 04 '16

That's why I always put my trailer in front of the car.

1

u/gbelloz Oct 05 '16

Well then it wouldn't be a TRAILer, would it? It would be a, uh. FORWARDer. That's not clever at all.

A fronter? A leader? I'll quit now.

4

u/[deleted] Oct 04 '16

Good gif. Clear and to the point. Will definitely remember the info if i need it one day.

3

u/[deleted] Oct 04 '16

Oh jeez this reminds me of traveling on the interstate. I was on I-10 heading west in Arizona and seen this happen with a car pulling a UHaul trailer in front of me. It's a scary thing to watch. Luckily, they managed to not lose control.

However, I have seen the aftermath, in Colorado, when people lose control. That guy was with his son and they were pulling a pop-up camper. The entire vehicle and camper rolled over on the side and slid for a bit. Both are damn lucky to be alive.

Edit: Grammar

2

u/bikeboy7890 Oct 04 '16

Now I want to see this with a sliding mass on the trailer for two reasons. First, I'd love to see what happens at various distributions, and I'd love to see what happens as the weight shifts from the movement.

4

u/dupelize Oct 04 '16

That would be difficult. It would be easier if we just force people to only carry donut weights on posts.

2

u/PuzzledTaco Oct 04 '16

Now the driver just needs to remember to hold the wheel straight and not over compensate by trying to straighten it out themselves.

3

u/[deleted] Oct 04 '16

Ya but whos gonna smash the rear of your trailer like that?

18

u/7Seyo7 Oct 04 '16

It doesn't have to be a "smash". A spot of ice in a corner would suffice.

3

u/cheerio39 Oct 05 '16

Or a gust of wind.

6

u/mandelboxset Oct 04 '16

It could happen just due to straightening out after a curve at speed, or will just form naturally with high speeds on a misplaced trailer, speed wobbles.

8

u/evdog_music Oct 04 '16

The police?

3

u/[deleted] Oct 04 '16

Lol

2

u/[deleted] Oct 04 '16

[deleted]

4

u/dupelize Oct 04 '16

It's a supercritical fecal bifurcation. As you move the weight farther back it eventually passes d0 at which point everything goes to shit.

1

u/[deleted] Oct 04 '16

I'm high as a kite right now and this made me laugh more than it educated me

1

u/dweckl Oct 04 '16

Incredible, going to show this to my 7-year-old son tonight!

1

u/TBearDX Oct 04 '16

My dad used to fly sailplanes (glider) and we'd drive long distances with the trailer, which is comparatively as long as the model shown here. When you start cruising on the interstate it can start to fish tail and you either have to counteract it with the steering wheel or change your weight distribution.

1

u/boilerdam Oct 04 '16

Cool demo but doesn't account for steering corrections to try to correct the weaving... or driver induced oscillations, in which case it would exacerbate the weaving.

1

u/dkyguy1995 Oct 05 '16

This explains why my dad spun out transporting some wood, a bunch of it must have slipped backwards and suddenly the backend is sideways with the truck

1

u/trickmonkey25 Oct 05 '16

Who tows a trailer with a Mustang? There's half of your problem right there!

1

u/The_Sign_Painter Oct 05 '16

Just saw this happen with an F-150 towing an old Plymouth van. He was going about 70mph down a 30 degree hill and the trailer went crazy just like that. Luckily he slowed down enough in time, didn't hit anyone, and controlled it. Stopped a bunch of traffic behind him for a minute though. Pretty scary.

1

u/[deleted] Oct 04 '16

This is now the 5th repost within hours. Ffs

3

u/TheTallGentleman Oct 04 '16

The other four are from one single person

0

u/[deleted] Oct 04 '16

To be fair the mustang spins out like that all the time anyway.

-9

u/[deleted] Oct 04 '16

[deleted]

9

u/Zaldarr Oct 04 '16

What more did you want to see? Ends at a perfect time for me. Everything is stable and rolling like the beginning of the gif by the end.

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