Jackknife with Hensley

3oaks wrote:

Exactly! All too often people think they know the facts without even knowing the details. More R&R in the campground would do a world of good.

Look at the picture, it shows the typical foot print of a jack knifed rig.

x96mnn wrote:
Where is it that people are seeing trailer brakes are designed to stop the weight of a trailer? I have never seen this, I have read they are designed for the assistance of stopping but they are not designed to bring a trailer to a stop per industry safty standards on their own.

Each axle has a GAWR (Gross Axle Weight Rating). and the brakes on each axle are designed to stop the weight that is on that axle. So, yes per industry standards the trailer brakes are designed to stop the weight of the trailer. A truck couldn`t handle stopping the weight of both vehicles (or even part of the trailer) because there are just too many variables for the manuf. to try and build the truck to match any given trailer. that is why the owners manual of a vehicle states you must have a trailer brake controller for a trailer if it weighs more than X amount of pounds!

And then there is the break-away switch that activates the brakes in case of a complete disconnect. you don`t want the trailer only having the ability of stopping 30% of it`s weight!

Tom/Barb, The photo looks like a typical jack-knife situation. How do brakes even figure into this? You can get to a jack-knifed situation and not have any brake issue on the truck or trailer. Road conditions like slick pavement can contribute.

Ken

x96mnn wrote:
Where is it that people are seeing trailer brakes are designed to stop the weight of a trailer? I have never seen this, I have read they are designed for the assistance of stopping but they are not designed to bring a trailer to a stop per industry safty standards on their own.

"IF" you are pulled over here in the states, ONE of the tests done to rigs with electric brakes to verify they are working,,,,,,, pull the ebrake lanyard, you start the truck in first gear, if the brakes hold the truck, or a tire does not rotate, you have a good system. If any tire rotates, You have a failed brakes system, and you are red tagged, ticketed as such. Your trailer can not leave the road unless it is on another rig! So you get to have it fixed on the side of the road, or PAY to transport the trailer to a repair shop, it can not leave the repair shop until the officer or equal is able to inspect the trailer, to show that the brakes work!

So in reality, the truck brakes stop the manufacture rated gvwr, the trailer brakes need to hold BOTH the trailer gvwr and the truck gvwr!

So not sure where you got the impression trailer brakes assist the tow rig per say......ie it can be less than the gvwr of the trailer, you are VERY WRONG on that one.

Marty

I won't tow a TT un less I have a HUGE DOG for the tail! I have rolled over with what I was told was proper load leveling and sway control.

I think people need to really think about what their TV is compared to the TT. Also I think people lead newbies to believe if you have a Hensley you can tow anything.

Compared to towing a 5er you need MUCH more DOG!

blt2ski wrote:


So in reality, the truck brakes stop the manufacture rated gvwr, the trailer brakes need to hold BOTH the trailer gvwr and the truck gvwr!



Marty

In your example, the truck is trying to over come the brakes which are holding back the trailer. It is not doing anything to assist the truck brakes. Better go rethink your physics.

As noted above, the brakes on the truck stop the max weight of the truck. The trailer brakes are rated to stop the max weight of the trailer.

Also, a magnetic brake will not create any braking force unless the wheel is rotating. The more rotation, the more braking force.

ken

Ken,

MY EXAMPLE< IS HOW the SP will check your blinken brakes IF you are pulled over and stopped! At least here in Wa st that is among three or 4 items you will have to show are up to par if they go after your electric braking system.

As I said, the trailer brakes had better stop, hold or otherwise, the gvwr of BOTH the truck and trailer!

Another test you will be put to, go to 20 mph, BOTH truck and trailer brakes had better stop the rig with in x feet! OR again, you have a failed brake system, tickets, and a tow bill to the repair shop. You must also have at least 11.4V in the battery that stops the trailer. IF you have drained house batteries, they are your braking batteries, and are below the 11.4V, you will not be allowed to go forward until you get new batteries, or you idle until the batteries are up to snuff!

MANY ways for the SP to get you off the road brake wise.

Marty

Tom/Barb wrote:

TXiceman wrote:

Where can you see that the trailer brakes failed? Ken

You only need to look at the picture to see that that trailer pushed that Ford SUV around like a toy. maybe the trailer brakes did not fail, maybe they were simply set wrong, either way, that trailer pushed that TV around into a jack knife and it will not do that if the brakes are working as they should.

Had he a dually we would not have this thread. that's my humble opinion.

You are so right!

Marty, the only way you will be able to see if the trailer brakes can stop the weight of the truck and trailer is to roll down hill and trip only the trailer brakes manually. The trailer brakes are not rated to stop that much weight. You are trying to add apples and oranges.

As for a brake failure on the Airstream and the jack knife, it is possible that on a wet road he tried to stop and had one of the inertia brake controllers. The truck can start to slide on the wet road and the inertia controller senses ZERO deceleration and does not send any voltage to the brakes. Then the trailer will try to get in front of the truck or jack-knife. I had a F350 dually and a Prodigy controller. Exactly as noted above on a wet street and I was 10 under the posted 45 mph speed limit. Light changed and I tried to stop. No trailer brakes yet and the trailer was starting to jack knife. I hit the throttle to straighten out the trailer and as I approached the next light, I manually worked the the trailer brakes while stopping. The trailer was a 35' Avion travel trailer with three axles. That was the last trip made with a Prodigy controller. Truck, trailer, brake controller and Reese Dual Cam hitch were all set up correctly.

From the photo of the jack knife, there is absolutely noway to say it was trailer brakes or what unless some of you have a really good crystal ball.

Ken

Cummins12V98 wrote:

Tom/Barb wrote:

TXiceman wrote:

Where can you see that the trailer brakes failed? Ken

You only need to look at the picture to see that that trailer pushed that Ford SUV around like a toy. maybe the trailer brakes did not fail, maybe they were simply set wrong, either way, that trailer pushed that TV around into a jack knife and it will not do that if the brakes are working as they should.

Had he a dually we would not have this thread. that's my humble opinion.

You are so right!

Hmm, when I had my Dually I didn't detect any magic anti jack knife towing dust...Not sure how having a Dually would have kept this particular event from happening either. Especially since we have 1 picture after the accident with no details.

I assure you a Dually can still jackknife....a crew cab Dually turns slower, handles worse, and possibly would have handle this event much worse than the expedition with its 4 wheel independent suspension. Ever seen a HD truck do evasive maneuvers with a trailer in tow compared to a(n actual) good handling vehicle? The Dually may have been on its top in this instance. At least the ex kept the rig on its wheels.

Just musing...since we are all speculating at this point.

Thanks!

Jeremiah