Anti-Jack Knife feature for RV type 5th wheels?

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Has anyone seen this setup that is for the big rigs... ?



http://www.safeeu.com/product.html



I was wondering if there was something like this for Trailers under 20K as with a short box if I jacked knifed with the Reese 18K slider forward I would destroy my trucks cab.



Why isn't there a built in "bump-stop" or something like this system for our light truck 5er hitches... ?



I would imagine, especially in the winter, I could jack knife my 44' trailer just like a full-size semi setup.
 
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I don't know if they are made for RVs, but have not seen one anywhere. However, I used to drive OTR and had the opportunity to pull a trailer that had this installed on it. I never had the chance to 'try it out' but I can tell you that it could put you in an embarassing spot if you forgot to disable it before getting into city traffic. If not disabled, and you start to turn, the steer axle will just get pushed along, and you won't be able to turn. The bad part is that to release the pressure on it, you had to flip the control switch, then back up trying to straighten the rig out to release the pressure on the fifth wheel and the safety 'pin'. Once the pressure was off, it would retract, then you could stop and go forward again, properly completing your turn.



To tell you the truth, I'm not sure that some of the lighter fifth wheels out there would withstand the strain.
 
Cummins4WD said:
I was wondering if there was something like this for Trailers under 20K as with a short box if I jacked knifed with the Reese 18K slider forward I would destroy my trucks cab.



Why isn't there a built in "bump-stop" or something like this system for our light truck 5er hitches... ?



I would imagine, especially in the winter, I could jack knife my 44' trailer just like a full-size semi setup.



Seems to me that there's no technology item that will take the place of good, careful, driving. Any tekkie-trick will have ramifications (no pun intended) that go beyond the problem for which it was built, and which could lead inexperienced drivers into thinking they don't have to think.



Nice rig and great-looking dog, by the way.



DBF
 
Cummins4WD, Tractor getting pushed into jackknife means you're trying to stop or slow down for something. Having jackknife bump-stops does nothing for tractor drive axles being pushed off line and entire rig is uncontrolable and you've still got to get stopped. In therory you could add power and drive out of jackknife if there's plenty of surrounding acerage and no obstructions. JimB.
 
JimB1 said:
In therory you could add power and drive out of jackknife if there's plenty of surrounding acerage and no obstructions. JimB.
Yep, been there and done that. Got the t-shirt (and the stained underwear) to prove it. 1996 3500 with a sticking right front caliper, a sudden thunderstorm and an inertial brake controller. I learned a lot that day! :--)



Rusty
 
Let me check my parts book here but I think that it is Reese that makes a special hitch for short beds. Whenever the trailer is turned one way or the other, the hitch automatically slides back. After I installed one, I test drove it and I know I could very easily jack knife it but in every day driving I wouldnt be worried about it.
 
TGibbs said:
Let me check my parts book here but I think that it is Reese that makes a special hitch for short beds. Whenever the trailer is turned one way or the other, the hitch automatically slides back.
I believe that's a Pullrite hitch.



Rusty
 
The Pullrite automatic slider is LESS likely to jacknife under deceleration than a reqular fifth wheel. In order to rotate, the trailer has to move back further from the truck cab.

Jacknifes require the truck/trailer combo to be under compression.



Not saying you can't jacknife one; it's just a little less likely.

Gary
 
For individuals new to towing. Any vendor claims and/or shop talk about jack kinfe resistant 5th wheel hitches is not good. What's a jackknive? Any time tractor drive wheels are pushed even 1 inch off line by the trailer. You're in a mostly out of control slide due to tractor being pushed and you're likely going to crash. No 5th wheel hitch can prevent the initiation of such events and only thing jackknife bumpstops might do is limit amount of angle between tractor and trailer while you're sliding into a crash. If jackknive recovery is remotely possible, having bumpstops limiting angle of jackknife might make recovery a bit more doable but you still need lots of highway open space. What isn't a jackknive? Under control, slow speed parking-positioning manuevers, forward and reverse, where sharp angles between tractor-trailer are developed. Bumpstops of various strategies might be handy here. What's most handy for these situations is you & rig get out into parking lot (leave co-pilot home) and practice until recognizing correct sight picture gives confidence. A few ground markers and stepping off distances is top notch self-teaching method. Under no circumstances should you be led to believe buying a certain 5th wheel hitch will allow jackknife protection on the open highway when it comes time to dynamite the brakes. Good luck, JimB.
 
JimB1 said:
You're in a mostly out of control slide due to tractor being pushed and you're likely going to crash. No 5th wheel hitch can prevent the initiation of such events and only thing jackknife bumpstops might do is limit amount of angle between tractor and trailer while you're sliding into a crash. If jackknive recovery is remotely possible, having bumpstops limiting angle of jackknife might make recovery a bit more doable but you still need lots of highway open space.



Jim is partially correct. You CAN steer out of a jackknife skid provided that the angle between the tow vehicle and the trailer does not exceed fifteen degrees. In my years on the road driving the big rigs, I've had the opportunity to do it more than once, and you can FEEL when it's doing it, you don't need to see it happening in the mirrors. In most cases, if you wait until you see it in the mirror, it's already too late.



Now, knowing that the key is to take corrective action BEFORE exceeding the 15 degree mark, early detection of the slide and quick reaction are paramount. Bump stops on the fifth wheel will not stop a skid, and will not help you to detect it earlier, but they will keep your rig from exceeding that magic 15 degree mark, giving you an extended opportunity to attempt to steer out of the skid.



Keep in mind that most jackknife skids are caused by one or more of the wheels locking up. In any skid, the sliding wheels will tend to overtake the wheels that are still turning. So, the first thing to do is GET OFF THE BRAKES and get all of the wheels turning again. If you have a manual transmission, push in the clutch pedal so that the engine is not keeping your drive wheels from turning at your travelling speed (this is a biggie on ice). Steer in the direction of the skid, just like you would if you were not towing a trailer, but then be ready to correct in the other direction, as with any skid.



I've driven well over a million miles in the big rigs since the late 70's, only shut down twice due to a snow storm, and never had a jackknife accident, though I've had to take corrective action more times than I can count or care to remember. I managed to do it without a device to keep the rig from exceeding the 15 degree angle though I would have been more comfortable with such a device. Bulletproof? Prevents loss of control? Invincible? Jackknife proof? No, no, no, and no, but my chances would have been much better, and it would have given me just one more advantage toward regaining control of the rig and averting disaster.
 
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