First Time Towing a 5th Wheel

[carhopper]

Good morning, I am a newbie at towing a 5th wheel trailer and I'm having some issues. I have a 2012 F350 Dually Powerstroke pulling a Voltage 3970 totaling about 18K right now. It has plenty of power and pulls up the hills in 6th gear sometimes so no problem there. I am getting what is referred to as chucking and bouncing. I have a Trailair system which I started with about 80psi. When going over a bridge or a concrete highway where there are sections, it began to oscillate forward and back until I hit the brakes. Also when I hit a really big bump, it took a deep dive and bounced until I hit the brakes. I stopped and aired up the Trailair to 95psi(the recommended fill mark) and that helped everything quite a bit. I'm still not happy with the stock rancho FX4 package shocks so I ordered some adjustable XL9000 shocks. Overall it is very stable with the dually, but the bouncing has to go. I should point out that the trailer is riding high by about 4" in the front. My hitch is as low as it will go so all I can do is raise the pin box a couple inches.

[donzinger]

Get your trailer as close to level as you can. You actually may be getting too much air in the TrailAire hitch. The upper and lower jaws should be parallel. Don't pay too much attention to the arrow mark on the shock (all advice received from Lippert tech). I also added two more shocks to mine to further dampen mine. The thing I did that made the biggest difference for me was removing all but three of my leaf springs and installing 8" airbags. Fully adjustable based on load. I-69 here in Michigan is tolerable with this setup.

[ATCguy]

I'm riding a tad high with my Voltage 3200 & F-450 too... and there's not much that can be done about it. As you say, the hitch is at its lowest setting, and my Pin Box can't be adjusted anymore either. I've pulled it across the country that way 4 times now, and no issues.

As for your chucking, that sounds as if you're getting more than you should. My F-450 is a little 'beefier' in the rear, but not by much. As for those bridges... yeah, there's not much you can do there except adjust your speed. Just like a sine wave, there's a certain speed where everything will move 'in time', just like the beat of a song. Depending on how wide the sections are on each bridge, and how much 'wave' there is in those sections... the speeds will be different.

Another factor to consider is the weight & balance of the rig itself. If you have a large majority of the weight towards the very rear of the rig (behind the axles)... the rig will tend to bounce more too. You'll have to play with various loads to get a feel that's ok for you.

Mine only 'chucks' on really big bumps... and then only for a bounce or 2. It's just part of the towing game.

[Tanman]

Same problem here with my Trailair and Voltage. I tow with a F250 and sometimes the chucking causes me to step on the brakes to stop it. The hitch is as low as it can go and the pin box as high as it will go yet i'm a little high in the front. I have no idea what else i can do. If I add airbags the rear of the truck will raise further raising the front of the camper. I just learn to live with it and yell Hang on while its bucking..

[carhopper]

Thanks for all the quick replies, this is a great forum. I looked at my pin box and it will go up about 2", that should get close to the 4" differential front to rear. I'll see how it does with the adjustable shocks too. When I did the XL9000s on my F250 last year it made a world of difference as they are huge compared to the stockers.

[Soccerloco]

I believe it's more of an issue of trailer loading. I haul in my toy hauler about 2500 lbs. As a result this decreases pin weight. At that point if you continue to stiffen up the rear of the pick up it only worsens
The chucking. What I had to do is load heavier items in the front trailer storage compartment. After doing that it helped tremendously. Of course road conditions play a large part in chucking as well. Unfortunately, I tow a lot in California, the roads there are absolutely pathetic. I regularly make a trip from northern Nevada to just south of San Jose. The bridge transitions are so poor it's almost impossible not to chuck. I just recently pulled to grand junction Colorado from N Nevada 780 miles each way mainly on rural two lane highways didn't have one chuck the whole way.

[mikesnider]

Filling Trailair hitch bag to 80psi (regardless of where that aligns to arrow) resulted in a smoother ride for me. Sure, a bit of bounce on bad bumps, but 1-2 times and it settles. On really bad bounces, I'll pinch the trailer brakes slightly to assist calming it down. (I'm a newbie, so hope that's ok to do).

Mike

[donzinger]

Mike - the important thing is you being comfortable towing and doing so within the safe limits of the tow vehicle and the trailer.

Tanman - Didn't raise mine as I removed all the helpers and now I can sit close to level with truck empty at 5psi and with the 3950 attached and loaded at 32-40psi depending on the load. Before and after pics...

[macman83]

You have to take into account the geometry of the hitch to understand what is actually causing the chucking. If you watch the plate when you hook up, you will see that it moves up and slightly forward, and so when pulling it it does the same. Also remember that the old solid hitches were much worse, because the frame of the trailer flexing causes the same type of movements. The airbag on the Trailair helps to dampen the up and down movements of the frame, but cannot totally eliminate it. Some chucking is inevitable, but leveling the trailer, adjusting the air in the bag, and even softening the springs and tires will help. Air pressure tends to push the trailer back in the hitch, and for every 10mph the air pressure supposedly goes up by 50%. If that is true, then you can bet there is a lot of pressure under the trailer at 65mph, and against the front cap. You are going to get it no matter what, and bridges and bumps will start the flexing and you can't stop that.

[wino]

Another thing to look at is get rid of the off road shocks, they're too soft. I would invest in a set bilsteins personally. A cushy shock made for soaking up bumps offroad and fifth wheel towing is kinda of the 2 extremes of the shock absorber spectrum. Air bags will help, also. Remember what the late Jerry Garcia of Grateful Dead fame said.......at least I'm enjoying the ride......

[Sinecure]

I have the same issue with chucking. I know the spots on the highway where it happens now and I do three things,which have completely eliminated 90% of the forces I feel in the cab. I know this sounds simple but it has worked for me.

1. Make sure your cargo is secured. If you have a vehicle in the garage, load the suspension
2. Slow down
3. Manually apply a little braking to the trailer brake controller.

[hilbilydavid]

I changed the rear shocks to Monroe Reflex and it really helped. As for not being level you can move the pin box and there is also a product called Correct Track that will give you 2" of lift on the camper. I had to do this on mine to help level it out, I have the big rig rims on it. The first time it happened to me my wife just about freaked out so I had no choice but figure out how to calm it down.

[carhopper]

I just returned from a 2,000 mile trip and I have it near perfect now. I can run 75 with no sustained chucking. First I raised the pin box so the trailer was level, installed Rancho 9000XL adjustable shocks, and increased the pressure in the pin box to 95psi. Bridge transitions at 75mph are still a good jolt, but it only bounces once and recovers. I run the shocks at 5 in the back and 3 in the front.

[sundancer 87]

75 mph is a tad fast to be pulling a Voltage unless you've upgraded to one great tire. OEM tires will leave the planet at 60 mph or less.

[carhopper]

It has the exterior package with tires below. I never felt uncomfortable and I did check them for heat and wear. I can't go 60.


7,040 LB Load Range E-Rated HD Tires

[eightydo]

carhopper; please read this thread there are 21 other similar.
http://www.dutchmenowners.org/forums...good-1006.html

[carhopper]

Thank you for the warning, you have me concerned now. I'll check to see the speed rating and manufacturer of the tires on mine.

[arlan in arizona]

Originally Posted by carhopper

I can run 75 with no sustained chucking.

You can, But I would not even consider it. If you want to run 75 MPH then consider the 17.5" wheels and tires.

Even then 75 MPH is to damn fast for a trailer.

I just retuned from a fairly long trip. I spent a lot of time at 55 MPH or less. When I felt pushed on two lane roads with semi trucks behind me I edged up to 65 MPH. I only have the 14 ply Goodyear G614's on a heavy triple axle trailer. The trailer tows great, but I can not keep from thinking about a tire being put to or past it's limits.

I pretty sure if you check the max speed rating of your tires it will be around 55 MPH.

Your fuel mileage will also increase a considerable amount when you slow down.

Try not to hurt yourself, your family or someone else.

One more thing. You would be wise to get your rig on a CAT scale and see where you are weight wise.

Best of luck to you and yours.

Arlan

[bigcntry13]

I could be wrong but I believe all ST tires have a speed rating of 65. I'm with Arlan though, 65 is max for me. And usually go slower. My thing is its hard to stop 25,000lb and going slower is easier. Enjoy the ride of owning an rv.

[Fanboy]

ST G rated taskmaster has an 87mph rating. They'll never see that