600 vs. 800 vs. 1200 lb trunnion bars?

[perryg114]

You want some of the porpoising. If you don't have it, then you have a very rigid setup that may damage your trailer. Instead of heavier spring and bars etc., consider putting heavy duty shocks on the back to damp out the motion. It never hurts to slow down. The load bars should get the tow vehicle level and help keep weight on the front wheels. You don't want the connection to be totally rigid.

Perry

Originally Posted by Landrum

I wonder if the spring bar rating has any affect on porpoising? I was setup by a dealer with 800-1200 bars for approx 550 lbs of tongue weight on a Toyota Sequoia. I don't carry water, but I have seen others post tw for a fully loaded 23fb around 750 (still under my current spring bar rating). I suppose I would rank the stiffness of the sequoia in the middle. I've been trying to research how to reduce the porpoising and I find a lot of suggestions for heavier spring bars or stiffer suspension on the vehicle (air bags or blistein shocks). After additional research, including this threads, it seems that heavier spring bars (which I already have) is bad for the airstream. So does this mean that if I get more flexible spring bars it will make the purposing worse?

I guess I just need a new airstream and new tow vehicle.

[Landrum]

I try to avoid interstates in a large part due to the porpoising. What I'm calling porpoising is a fairly quick/rapid bounce in the middle row of the sequoia. The wife and myself can feel a little in the front row, but the kids really bounce. What I don't know is whether that rapid bouncing is transferring to the front of the airstream. I would think that shaking, if it is transferred to the AS, would be bad for the airstream?

[mje]

Checking in, while on topic, is ProPride with 1400# bars a good fit for my 2013 VW Touareg towing 2014 27' FC that I have on order?

[Doc Foster]

Still a bit confused, but think I will stay with the 1200 lb bars, as "suggested" by the Reese chart provided by Wayward. I did find that chart as everyone was posting replies. I can always switch back to my 600 lb bars on a quick weekend trip to see the difference.
Thanks for all the input!
Now time to accessorize and stock my Flying Cloud, my first Airstream and hopefully last trailer!

Originally Posted by Wayward

I am not buying that late model steel framed Airstreams are are somehow fragile to WD setups. The frame thickness and section on my Airstream is larger than on my 10,000lb cargo trailer.

So...seeing I've got pretty much the same weight trailer as Doc Foster I looked up the Reese info on my DualCam HD setup. Below is their recommendation chart.

The 25' FB has a dry tongue weight of 720 lbs. If I add 60lbs for propane, 50 lbs for other fluids and then 100 lbs of cargo in the bed, I am at 930 lbs according to the number Reese wants.

That, according to the Reese chart puts me smack in the middle of the 1200lb bar range and far outside the 800lb bar range.

It looks to me like my Airstream dealer knew what he was doing and selected the correct bars at 1200lbs, as did Foster's.


Attachment 204517

Attachment 204516

[Wayward]

Originally Posted by Doc Foster

Still a bit confused, but think I will stay with the 1200 lb bars....

My state of mind as well

Originally Posted by Doc Foster

I can always switch back to my 600 lb bars on a quick weekend trip to see the difference.

If you do try the 600lb bars, please post your experience on this thread. After reading this thread, if I had some 600 or 800 lb bars I'd certainly run them for a wile to see how the rig behaves. But I've not noticed any of the problems to warrant buying some.

[Doc Foster]

Originally Posted by Wayward

My state of mind as well
If you do try the 600lb bars, please post your experience on this thread. After reading this thread, if I had some 600 or 800 lb bars I'd certainly run them for a wile to see how the rig behaves. But I've not noticed any of the problems to warrant buying some.

I will post my experience, but won't be until spring. Too cold and too much snow right now, can't wait for spring!

[RLS]

Has anybody have the experience of switching to the heavier bars and stating how much better the ride was?? I've only seen the opposite being stated on this forum.

[youngpeck]

Wayward, what setup do you use when you pull with your F250? I have yet to purchase anything. My mechanic, who I trust, and who pulls (not an AS, however) lots of stuff with his F350, says I don't need anything with my F250 V10. I did pull my AS over 300 miles when I bought it--dipped the rear end maybe four inches, but pulled beautifully at 65 mph. I'm thinking if/when I do get a WD hitch it will be as light as possible.

Thanks

[Wazbro]

Originally Posted by Landrum

I try to avoid interstates in a large part due to the porpoising. What I'm calling porpoising is a fairly quick/rapid bounce in the middle row of the sequoia. The wife and myself can feel a little in the front row, but the kids really bounce. What I don't know is whether that rapid bouncing is transferring to the front of the airstream. I would think that shaking, if it is transferred to the AS, would be bad for the airstream?

That changes things, when I think of porpoising I'm thinking more the front end bouncing. With the back end of the TV bouncing I would say that is a symptom of too much weight distribution, taking too much weight off the rear axle. So it seems your 1200 lb bar are too much or at least adjusted too tight. Bar rating goes by the most weight they are rated to distribute so 801-1200lb would be 1200lb bars.

[perryg114]

It would help if he measured the actual tongue weight so we know what we are dealing with.

Perry

[Wayward]

@ youngpeck "what setup do you use when you pull with your F250?"

I suspect my Safari has quite a bit more tongue weight (700-900 lbs) than your trailer so while I can pull with no WD, it does squat alot. On my F150 it pretty much bottoms out the rear suspension with no WD.

The thing here is tongue weight. In some ways your mechanic is right but may not understand just how much tongue weight an Airstream is set up with.

For example, I have a utility trailer that pulls at 10,000lbs, loaded. I do not use any WD or anti-sway with it. That is much more total weight than my Airstream, but I am able to adjust the cargo distribution inside to keep the tongue weight from squatting the truck.

Same with large boats which have a few trailer adjustments to manage tongue weight.

I use the same WD/anti-sway set up on both the F150 and F250. The only difference is that I tighten the chains up a notch or two on the F150 to transfer more weigh to the front than I need to on the F250.

It is a Reese Dual Cam setup with the 1200lb WD bars that also do double duty as anti sway bars.

The Airstream needs WD even on the F250 for a comfortable towing experience. Now....even though I do not need WD with the 10,000lb utility trailer, there have been times on the highway when anti-sway bars would have been nice.

So if you were to go with something like the Reese Dual Cam you would get the antisway, and could pick the a set of WD bar weights that match to your Airstream. The Reese chart I posted above gives a way to calculate the applicable tongue/cargo load for your airstream . It sounds like from the experiences posted here you could go with a lighter bar than what Reese recommends if you wanted to.

[Landrum]

Originally Posted by perryg114

It would help if he measured the actual tongue weight so we know what we are dealing with.

Perry

I have measured my tw at 550 with a Sherlin (sp?) scale. We pack pretty light and don't carry water.

It seems in my case the setup is too stiff. The bumps of the concrete joints are transferring into the vehicle and not being absorbed by the tires, shocks,etc. I have been so worried about my GYM's based on stories about tread separation I've been running my GYM pressure at 50. I could reduce that quite a bit based on my actual axle weights. I was hoping to avoid wasting money, but I think I need to bite the bullet and try lighter bars. I also think I'll reduces tire pressure slightly on the AS and TV. I may start with tire pressure as a test first to 'see' what the effect is.

[youngpeck]

Wayward:
Thanks for uploading the charts. I suspect my Caravanner tongue weight is in the 600-800 range. When the weather breaks here this spring I will attempt to get a real weight on it. And I agree that my mechanic probably doesn't quite understand the AS dynamic. My F250 has beefed up rear springs and heavy duty shocks, but I'd still like to use a WD hitch. I like the idea of the Reese being adjustable. Now I understand that towing and hitch systems are probably some of the most discussed subjects on this entire forum, but I haven't seen anything that deals with off-pavement towing. What I have in mind is this: at low speeds on bumpy gravel roads or jeep trails (I'm talking real boondocking, I guess) would said WD hitch system at all hinder the pulling of a trailer? I've read on other threads how some guys get nervous when they have to back into a high-pitched driveway. Some of my friends take their big horse trailers into some remote areas, and I want to be able to join them. Is the solution to undo the WD hitch on backroads and trails such as these?
Thanks again for your thoughts. I'm getting quite an education here.

[Wayward]

Towing offroad is not something I have done. Like the driveway issues you mentioned, a gully on a sharp grade offroad could be tricky.

The WD bars do stiffen the pivot point between trailer and truck but it does still move. The tension on the bars is adjustable.

If your buddies are towing horse trailers I gotta assume they are on trails rated around 3 or less. Since you already know your rear suspension will handle the tounque weight, you have the options of loosening the WD bars when you get to the trail, or even removing them if they start to bind up.

Jut remeber as you loosenin the WD bars weight moves back so your front drive wheels will lose traction an you rea rwill gain it in 4WD.

You might want to start a new thread on towing off road with WD. That ought'a be real interesting discussion

[Doc Foster]

Originally Posted by perryg114

It would help if he measured the actual tongue weight so we know what we are dealing with.

Perry

I asked my RV dealer and they did not have a tongue scale, and I don't have $162.09 laying around for a Reese 5780 Trailer Tounge Weight Scale : Amazon.com : Automotive

It seems like any good RV dealer that is wanting to properly set up weight distribution hitches should have one, shouldn't they?

[dkottum]

Originally Posted by Doc Foster

I asked my RV dealer and they did not have a tongue scale, and I don't have $162.09 laying around for a Reese 5780 Trailer Tounge Weight Scale : Amazon.com : Automotive

It seems like any good RV dealer that is wanting to properly set up weight distribution hitches should have one, shouldn't they?

A good RV dealer could rightly assume your Airstream model tongue weight is 835# empty with no options and a customer may well add 200# or more to it, and install 1200# to 1400# tapered bars to ensure you are able to transfer enough weight with your 1/2 ton truck to ensure good steering control on slick roads and your headlights are not lighting the tops of the telephone poles.

The relatively soft suspension of the 1/2 ton and trailer tire pressures recommended by the tire manufacturer will help ensure a soft ride for your Airstream. Road condition matters and it is getting tougher to find decently smooth roads these days but we can try, and control speeds when we can't.

[youngpeck]

Originally Posted by Wayward

If your buddies are towing horse trailers I gotta assume they are on trails rated around 3 or less. . . .
You might want to start a new thread on towing off road with WD. That ought'a be real interesting discussion

Thanks for the link to the trail ratings. I've not seen that before (or perhaps I have but not realized it) and I've been off-roading for the nearly forty years I've lived in Utah. Your hunch is about right--three- and four-horse trailers need a fairly decent trail, and do not have much clearance. I figure I can go where they can, if I'm very careful. I'm not nearly as adventurous as I once was, but there are many out-of-the-way places in this part of the country that will accommodate boondockers in a safe fashion.

Thanks for your suggestion about starting that off-road WD thread. I'll take a couple of days to collect my thoughts and then get to it.

[overlander64]

I have towed my '64 Overlander Land Yacht International with three different truck-based tow vehicles since its purchase in 1995. Initially, I towed with the hitch as set-up by an independent hitch shop that included 1,000 pound weight distribution bars with a standard Reese Hitch and friction sway control. I didn't give this set-up much thought as it paralleled the set-up utilized by the trailer's original owners (1964-1980) the only difference being the tow vehicles that they utilized included:

• 1957 Mercury Monterey
• 1967 Mercury Monterey
• 1970 Mercury Monterey
• 1975 Oldsmobile 98

The second owner towed the Overlander very sparingly with their 1/2-ton, 2WD Ford pickup so there were probably only about 20,000 miles towed behind that vehicle.

I noticed few problems with the heavier hitch set-up with my first truck-based tow vehicle, a 1984 Jeep Grand Wagoneer with 360 V8 with 4bbl. carburetion and 3.90 differentials. The Grand Wagoneer and Overlander were quite happy together, but fuel mileage was horrible at 6 to 8 MPG when towing and a best of 10 MPG.

The difference when I upgraded to a brand new 1995 Chevrolet K1500 with Z71 package was immediately noticed. The truck had the heavy duty trailering package with a 6,000 pound trailer tow rating (5.7 Liter V8/3.73 Differentials). Regardless of how that hitch with 1,000 pound weight distribution bars was adjusted the result was the same . . . closet door popping open while traveling, pillows deploying to the floor regardless of where they began travel, cabinet doors popping open, and draperies opening and closing on their own. While this was disturbing, I couldn't find anyone who could answer my questions about why the trailer seemed to be riding so roughly . . . I had never heard the original owners' speak of such problems in all of the years that they owned the trailer (they were long-time friends of my family).

The 1995 Chevrolet was traded on a brand-new 1999 GMC K2500 Suburban with 7400 VORTEC and 4.10 Differentials as well as the heavy duty 10,000 pound trailer towing package. The difference between the 1999 and its 1995 predecessor was remarkable. Despite its much higher trailer tow rating, the Suburban rode much better and transmitted fewer road vibrations to the trailer (the Suburban was ordered without the Z71 package or other heavy duty spring packages beyond that required in the trailer tow package). The problem with rearranged pillows and draperies was significantly lessened, but not eliminated. I finally was prompted to search for a solution to the problem when a stress crack began to form above the entry door on the interior skin. I was 500 miles into the trip to the 1998 WBCCI International Rally in Boise, Idaho when the crack began and it continued to get worse as I approached Boise. While in Boise, I was fortunate to encounter a long-time Reese representative who reviewed my set-up and determined that the 1,000 pound bars were much too heavy for my set-up. It was suggested that I go with 600 pound weight distribution bars and I had a Reese Dual Cam system installed at the same time to replace the friction sway control that was more of a nuisance than help. The change was immediately obvious on the tow home. Everything stayed where it belonged with minimal shifting while underway . . . and the stress crack stopped spreading.

The restoration and changes to my Overlander left the trailer weighing 6,000 to 6,100 pounds when loaded for an extended vacation, and the hitch weight fluctuates between 725 and 775 pounds depending upon how much LP is carried and the distribution of weight carried in the trailer. One of the changes that had the most impact on hitch weight was switching from 30 pound to 40 pound LP tanks while the installation of a slightly larger Dometic 3-way refrigerator had a modest impact upon hitch weight . . . most of my heavier equipment resides either over the axles or slightly ahead of the axles. With fifteen years of use, no particular issues have been noted with approximately 40,000 miles of towing with the Suburban.

Good luck with your research and investigation!

Kevin

[Wayward]

Originally Posted by Doc Foster

I asked my RV dealer and they did not have a tongue scale, and I don't have $162.09 laying around for a Reese 5780 Trailer Tounge Weight Scale : Amazon.com : Automotive

I have heard folks here talking about measuring tongue weight this way......

[Landrum]

So I've got a dumb question. What exactly is the effect of lighter bars? Do heavy bars create a 'pinned' (or rigid ) connection between the AS and TV and allow less vertical movement?