5th Wheel Towing Issue Crossing Interstate Highway Bridges and Overpasses

[Harley Bob]

I just joined this forum after reading several comments on towing issues related to 5th wheels. The group and respondents provided knowledgeable information, and as Bill O'Reilly says on the Fox channel, no one bloviates, but simply provides useful information.

Anyway, I have a 2003 Thor Toy Hauler, 33 foot 5th wheel, that I tow with a 2002 Chevy 2500HD, Duramax. I've added Bilstein shocks and air lift bags to improve towing, and it seems to have helped. However, a major issue, and really the only issue I have, is the bounce to the truck that occurs sometimes when crossing some of the overpasses and bridges on our great interstate system, i.e. I-80, 25 in southern Colorado, I-40 in Arizona. I've read about the air ride king pin hitches, and air ride 5th wheels, but I'm not convinced that these will solve the problem. I'm looking into adding more king pin weight, closer to 2700 lbs to see if this helps. Currently, I'm around 2100 lbs with empty gray and black tanks, and water in only the water tank forward of the front trailer axle. With the toys loaded, I'm around a Gross trailer weight of 13000 lbs.

Suggestions or comments?

Thanks

[Harley Bob]

I just joined this forum after reading several comments on towing issues related to 5th wheels. The group and respondents provided knowledgeable information, and as Bill O'Reilly says on the Fox channel, no one bloviates, but simply provides useful information.

Anyway, I have a 2003 Thor Toy Hauler, 33 foot 5th wheel, that I tow with a 2002 Chevy 2500HD, Duramax. I've added Bilstein shocks and air lift bags to improve towing, and it seems to have helped. However, a major issue, and really the only issue I have, is the bounce to the truck that occurs sometimes when crossing some of the overpasses and bridges on our great interstate system, i.e. I-80, 25 in southern Colorado, I-40 in Arizona. I've read about the air ride king pin hitches, and air ride 5th wheels, but I'm not convinced that these will solve the problem. I'm looking into adding more king pin weight, closer to 2700 lbs to see if this helps. Currently, I'm around 2100 lbs with empty gray and black tanks, and water in only the water tank forward of the front trailer axle. With the toys loaded, I'm around a Gross trailer weight of 13000 lbs.

Suggestions or comments?

Thanks

[RV Wizard]

Harley Bob, welcome to iRV2.com. We are glad to have you join us here and look forward to reading of your adventures and experiences. While I am no 5th wheel expert there are those on this forum that can and will help once they see your post. Good luck and I am sure you will enjoy this site as much as taking out your toy hauler.

[JimmyDee]

I added shocks to the 5er and that took that bounce out of the truck. One of the best mods I've ever done for comfort and control.
Jim

[powerboatr]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Harley Bob:
I just joined this forum after reading several comments on towing issues related to 5th wheels. The group and respondents provided knowledgeable information, and as Bill O'Reilly says on the Fox channel, no one bloviates, but simply provides useful information.

Anyway, I have a 2003 Thor Toy Hauler, 33 foot 5th wheel, that I tow with a 2002 Chevy 2500HD, Duramax. I've added Bilstein shocks and air lift bags to improve towing, and it seems to have helped. However, a major issue, and really the only issue I have, is the bounce to the truck that occurs sometimes when crossing some of the overpasses and bridges on our great interstate system, i.e. I-80, 25 in southern Colorado, I-40 in Arizona. I've read about the air ride king pin hitches, and air ride 5th wheels, but I'm not convinced that these will solve the problem. I'm looking into adding more king pin weight, closer to 2700 lbs to see if this helps. Currently, I'm around 2100 lbs with empty gray and black tanks, and water in only the water tank forward of the front trailer axle. With the toys loaded, I'm around a Gross trailer weight of 13000 lbs.

Suggestions or comments?

Thanks </div></BLOCKQUOTE>
I would take it to a certified scale and see what your pin wt and loaded axle weights are when your loaded up and ready to go., is your fresh tank very near the axles or way up forward towards the pin?

if your toy are onboard and your full of water, I would imagine the fulcrum effect of the toys out back is causing you to be a little lite on the pin. which is causing it to lift and bounce around.
You may find that some weight needs to be moved forward.
we run close to and sometimes over 2500lbs on our pin, makes a world of diffeence on rough roads

[charliez]

2700 pounds of pin on a 2500? Sounds like you need a diffrent tow vehicle.

[Harley Bob]

Thanks guys. I do have shocks on the trailer, supplied by the OEM. Checked them out about six months ago, and they seemed to be working, or at least they were providing reasonable resistance.

I do believe Robert's suggestion regarding king pin weight is on the right track. Unfortunatly, both water tanks are right near the axles on the trailer, one fore and one aft. I have split them and only use the forward tank when hauling toys, and while it probably helps, it's not enough. I'm in the process of putting about 400 lbs of sand right over the king pin in the storage area under the forward berth. Hate to have to haul dead weight around, but it may be the only solution. And, I do need to cross a scales again to see what the final weight and balance looks like.

Again, I appreciate the comments and suggestions,

Harley Bob

[powerboatr]

harley bob
Before i add sand bags,
I tried to find your floor plan, does your have the two slides with couches??
anyway i would move heavy food forward, canned sodas or adult beverages add up fast,

How heavy are the toys out back? do you place them as far forward as possible and is your rig tripple axles or double.
any who, i would add FOOD instead of sand, I like to eat

[charliez]

All your talking about is the bouncing as you cross over an overpass? Your going to add all this weight so your rig dosen't bounce for about 150 feet of a thousand mile trip?

Your words "crossing some of the overpasses and bridges"

Do you ralize your killing your mileage eve nmore. Why don't you just slow down about 5 mph? Sure seems like alot of trouble to go thru for not much % of the road surface you actually drive.

[Ray,IN]

Your post indicates you have your 3/4T pickup maxed out. This makes the bounce unavoidable. I like charliez' suggestion.

[knute]

Sorry, guys.

A Chevy 2500HD can handle about 3700lbs. I seriously doubt he is over weight of the truck.

I think your trailer is heavy in the butt. This makes the pin light.

Shift some weight around, towards the front. Do a test tow. While doing the test tow, swing into a scale. Get all axles wieghed while hooked up and get the truck weighed without camper. Do some math and you'll have all the weights needed.

You have enough truck. The problem is likely loading of the trailer.

One more thought occured to me. You may have stiffened the rear suspension on the truck too much. Try dropping some air out of the lift bags.

[jimtoo]

I am running with about 2900 on the pin. But I also have a Trailair pinbox. I think the trailair does a great job, and reduced it by at least 75%, but did not take it all out. I don't think anything will remove it all. Keep the weight up on the pin, but nothing will eleminate all the bounce.

[charliez]

You have 2,500 pounds of pin weight on your 3/4 ton truck? (3/4 ton = 1500 pounds).

Please keep you rig away from my family and freinds. I'd like to keep them alive.

[NLOVNIT]

If I may put my 2cents worth in on truck designations/classifications. I'm not an expert,& maybe someone that knows for sure can either confirm or deny my statements. But, from what I do know, the categories of 1/2 ton, 3/4 ton & 1 ton do not mean today what they did back when the terms were originally coined. Way back "in the day", yes, a 3/4 ton truck was rated to carry 1500 lbs of stuff (as stated in charliez's equasion); 1/2 ton meant 1000 lbs...etc. But trucks have come a long, long way since then. 1/2 ton, doesn't necessarily mean rated for only 1000 lbs. It could be more, it could be less depending on the actual options (like axles, springs, tires...etc)& other items on the vehicle. We still refer to the sizes as 1/2, 3/4 & 1 ton, but they don't necessarily mean what they used to. At least that's what I understand about trucks.
L-