Pulling doubles

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samthetramp

samthetramp

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I searched 1st but no luck. Does anyone have actual experience pulling a small cargo trailer behind a 5ver? I'm considering getting a motorcycle and don't want to trade to a toy hauler for several reasons. I can see how this could get ugly quickly yet it's done every day by truckers. I have a Montana3971RD that has a factory installed receiver on the back. I'm thinking a trailer with the axle set as far back as possible to help cut down on sway and a anti sway hitch would be a given.
 
I have not but have a friend who did tow a large fifth wheel with a small car behind that with a heavy truck conversion and he recommends against it. He had brakes on the car but said that the main problem was that the trucks that tow multiple trailers have progressive braking that engages back to front and he pointed out that the trailers that are towed that way all have an axle both front and rear. He has since changed trucks and has his car on the truck just behind the cab.
 
Before you get too wound up in this plan, do the research. FMCA and Trailer Life might be good starts. When I used to tow sailboats all over, I frequently ran into states with different laws.
Matt
 
Kirk said:
I have not but have a friend who did tow a large fifth wheel with a small car behind that with a heavy truck conversion and he recommends against it. He had brakes on the car but said that the main problem was that the trucks that tow multiple trailers have progressive braking that engages back to front and he pointed out that the trailers that are towed that way all have an axle both front and rear. He has since changed trucks and has his car on the truck just behind the cab.
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Trucks don't have back to front progressive braking, just fully proportional brakes that engage simultaneously with the tractor brakes.

The confusion may be that the inertial brake controllers used with many RV trailers have a built-in delay - they have to sense the tow vehicle starting to decelerate before they apply the trailer brakes.

Because of their much longer lengths trains use a three way valve control valve on each car to apply air pressure directly to the brakes from local tanks, minimizing the propagation delay down the length of the train's air lines. Trucks don't, their brake application pressure originates at the tractor and flows rearward directly to the trailer(s) brakes.
 
Kirk said:
Progressive may be the wrong choice of term, but are you telling us that the driver is not able to apply braking to the rear trailer only?
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If there are multiple trailers, not to the rear trailer by itself. The driver can apply all of the trailer brakes independent of the tractor brakes via a lever on the steering column, just like using the manual override on an RV trailer brake controller. But normally he just steps on the brake pedal and the tractor brakes and all of the trailer brakes apply simultaneously.

RVers get the same effect with a controller that responds directly to brake line pressure. You don't feel the trailer brakes engage because they activate simultaneously with the tow vehicle brakes. You do feel the trailer brakes come on with an inertial controller because of the short delay before it activates the trailer brakes.
 
OK, the main difference between pulling a second trailer behind a RV 5th wheel vs. a commercial truck pulling double trailers is the hitch location of the second trailer. Commercial trucks have their wheels located at the rear of the trailer - RVs have a long rear overhang that swings back and forth.

Multiple trailers have an effect called "crack the whip". Small changes in the tow vehicle's direction, such as moving the steering wheel back and forth to stay in a lane, can be amplified as the changes move rearward through the combination. Commercial drivers are trained to hold the steering wheel steady instead of doing this. The crack the whip effect is even more pronounced with a second trailer behind an RV 5th wheel trailer because of the long rear overhang amplifying the action at the second trailer's hitch point. Adding a sway control there won't change it.
 
Aren't there licensing differences for towing the extra trailer from state to state? Seem to recall that some states require a Class 1 Trucker's license for this.
 
Reinigm said:
Aren't there licensing differences for towing the extra trailer from state to state? Seem to recall that some states require a Class 1 Trucker's license for this.
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Yes, but as long as you're legally licensed to drive the combination in your home state other states will honor your license in theirs. This doesn't help if the combo is illegal in that state, though.
 
Ok lots of great info given. Not seeing how train brakes relate to truck brakes unless there's some type of a delay valve between the front and rear trailer brakes. Maybe there's an electric device for such a situation? I don't know. The placement of the axles on the 5ver I can see definitely having an unwanted effect. Guess I'll abandon this plan.

Thanks
 
samthetramp said:
I searched 1st but no luck. Does anyone have actual experience pulling a small cargo trailer behind a 5ver? I'm considering getting a motorcycle and don't want to trade to a toy hauler for several reasons. I can see how this could get ugly quickly yet it's done every day by truckers. I have a Montana3971RD that has a factory installed receiver on the back. I'm thinking a trailer with the axle set as far back as possible to help cut down on sway and a anti sway hitch would be a given.
Click to expand...
Have you considered a motorcycle carrier. That's what I have. Motorcycle Carriers
 
The other legal issue is that some states don't allow towing doubles at all (at least not outside of the National Highway System where federal rules apply). This is a "rules of the road" kind of thing, so reciprocity with other state's laws doesn't apply. I see Lou mentioned this, though more succinctly.

There are lots of reasons why this is a rather risky thing to do with a rig like yours. It is NOT in any way comparable with commercial rigs with doubles-towing equipment (as Lou has explained). Further, I think your idea of a trailer with its axle far back just exacerbates the "snap the whip" effect of a 2nd trailer hooked to a hitch that itself is far back from the axle. Nor do I think an "anti-sway hitch" is going to make a difference.

I think this is something I would do only if it were really critical to my needs. Nor would I risk it often. I see guys taking their RV and boat to a campground for a long vacation or a season and think "maybe worth it", but it's still pushing their luck. If they ever had to stop quickly for some reason, I'm pretty sure no good can come of it.
 
Tileman.
Are you in a motorhome or a trailer? If a trailer how does having all of that weight on the back work out? I can't imagine putting a big bike on the back of my rig without having massive problems with tail whip.
 
samthetramp said:
Tileman.
Are you in a motorhome or a trailer? If a trailer how does having all of that weight on the back work out? I can't imagine putting a big bike on the back of my rig without having massive problems with tail whip.
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Of course, you're right. Mine is on a motorhome.
 
Tom said:
be aware that some folks call it triple towing v double towing.
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And some find that terribly confusing or simply get hung up on the language. Think of it as towing double trailers, so you end up with a triple vehicle rig, i.e. a tow vehicle plus two more things under tow. It's the same thing no matter how you word it.
 
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