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brunoffrance · 03-05-2005, 03:18 AM

Hi the community;

My project , for the next summer season, is to tow my 27' Overlander with my Ford F150 and to carry , my last buy , an Harley Davidson on the pick-up trailer...
So, when I couple the A/S on the hitch ball, the rear of the F150 get down seriously. With the weight of an HD Heritage Softail, i think it'll be dramatic.
I can set the level horizontaly with my stabiliser chain system but I've heard it was possible to equip the truck with air suspensions, in complementarity of the classic spring suspensions; last year I've taken my m/c YAMAHA like that but now, with an HD, the weight is very different !

Is there anyone who has made this kind of equipment and is it really a right way or
how you do to carry your motorcycle with your airstream ?

thank you, by advance for your future advices .

Bruno.

overlander64 · 03-05-2005, 08:04 AM

Greetings Bruno!

Quote:

Originally Posted by brunoffrance

Hi the community;

My project , for the next summer season, is to tow my 27' Overlander with my Ford F150 and to carry , my last buy , an Harley Davidson on the pick-up trailer...
So, when I couple the A/S on the hitch ball, the rear of the F150 get down seriously. With the weight of an HD Heritage Softail, i think it'll be dramatic.
I can set the level horizontaly with my stabiliser chain system but I've heard it was possible to equip the truck with air suspensions, in complementarity of the classic spring suspensions; last year I've taken my m/c YAMAHA like that but now, with an HD, the weight is very different !

Is there anyone who has made this kind of equipment and is it really a right way or
how you do to carry your motorcycle with your airstream ?

thank you, by advance for your future advices .

Bruno.

The more important issue (IMHO), is whether you will be exceeding the rear axle weight carrying rating or the Gross Combined Vehicle Weight Rating once your Overlander is hitched - - the rear axle capacity as well as GCVWR information should be in your truck's owners' manual and/or on a placquard mounted to the vehicle. Another factor to consider is that the air springs will quite likely increase the stiffness of the rear suspension which is something that can pose problems with Vintage Airstreams by adding more towing stresses to the coach's chassis.

While air springs such as "Air-Lift" can help to compensate for the "squat" that results from the load in the bed, they do not increase the weight carrying capacity of the chassis. I have Air-Lift springs on my Cadillac only because its very soft suspension has too much movement (prior to adding the air springs, it wasn't uncommon for the wheelwells to contact the edge of the tires as a result of this motion) - - the air springs are inflated to just slightly above their minimum inflation pressue to reduce the suspension movement when towing my Minuet (basically, I follow the instructions for hitching in the Eldorado's owners' manual as it had factory level-ride). The key with the air springs on my Cadillac is to load the tow vehicle and then adjust the air springs prior to hitching the coach - - once the coach's tongue is on the ball mount, all adjustments are made through the weight distribution system. On my Cadillac, I am well below the weight limits as my coach's gross weight is 3,100 pounds (well below the Cadillac's maximum trailer tow rating of 6,000 pounds), and just under its maximum hitch weight of 600 pounds (the Minuet has a gross hitch weight of 525 pounds).

Good luck with your investigation!

Kevin

Condoluminum · 03-05-2005, 11:08 AM

Bruno-

During WBCCI event in Pasadena over New Year holiday, we met gentleman traveling full time with Chevy Pickup, Airstream Classic 34' trailer, and Harley Davidson Fat Boy in bed area of pickup truck... WIth his generator, Satellite TV system, flat screen TV and Laptop for WiFi e-mail, he was pretty self-sufficient...

While weights are an issue, F-150 should be able to manage gross weight, as most Harley's are in 350kg range, centered in bed.. Two ideas he employed that I thought were valuable were:
a) He had custom "tall" aluminum shell cover built for pickup bed area, so motorcycle was enclosed and lockable when traveling or not in use.. SImilar to metal boxes used by campers and others, but about 1 meter taller to allow him to roll motorcycle up ramp and onto bed of truck.
b) He also interviewed motorcycle dealers and customizers and concluded that wide metal "mesh" ramp (equal in width to tailgate on truck) was simpler and safer way to load and unload motorcycle... He could power up or walk backwards down ramp without fear of losing balance and tipping. These are also available from motorcycle accessory shops..

We use Gabriel brand "Air Adjustible" rear shock absorbers on Chevy Suburban to manage ride height and ride quality, and they are effective. Approx cost to install pair in rear is $150 in parts and labor...

John McG

Coastalview · 03-05-2005, 07:58 PM

This topic has been discussed before. Air assisted suspensions systems only help stabilize loaded vehicles, and not increase load capacities. We currently have air bags on the rear of our pickup, from previously having a cab over camper.(now we rather tow our bed than carry it!). The air bags helped with stability, but they don't create the ability to increase your load capacity. I've seen pickups with these air bags over inflated, creating frame cracks at the mounting plates to the frame, because the entire rear pickup weight is entirely transfered to this location. Also it has been mentioned that the utilization of these rear air bags with Airstream towing in mind, can cause the undersirable stiff towing, rather than the soft towing needed to keep these trailers from rattling apart. Depending on what additional weight we carry in the back of our truck and towing our Airstream, I can generally figure what amount of psi. I can inflate the air bags on our truck,(only for stability mind you) without creating a stiff ride for our trailer. Good luck, but I think yor going to be pushing your F-150 pickups gross vehicle weight. Jeff

brunoffrance · 03-06-2005, 08:39 AM

OK for the informations, you're, as usual, great;
I've visited the web sites of Airlift and firestone anr i 've found an other way, may be very simple in his conception, but apparently, very efficient: "TIMBREN";

http://www.timbren.com

Do you know or to you use that ?
Tell me what you think about this simple rubber suspension .

thank you one more time,

bruno;

brunoffrance · 03-09-2005, 11:15 AM

Finally, I've made my choice for the TIMBREN kit ;
Very cheap : $143,95 and international air mail shipping: $61,15 at:

www.truckspring.com

I've read other threads on this system on other trailers site web, especially 5th wheels owners and they were very satisfy ;
Easy to install, lifetime guaranty, no trouble with air leaks or so... all the timbren system owners 'ldnt want an air suspension kit instead.
here is the information i want to share to the Airstream Community

Bruno.

Inland RV Center, In · 03-09-2005, 02:51 PM

Rear end suspension modifications "CAUSED" two thirds of "ALL" the loss of control accidents, involving towing an Airstream trailer.

This data was obtained from losses over a 10 year period of time.

Specifically, if you add air shocks, or air bags, to the rear end suspension, and inflate them beyond minimum pressure, you progressively destroy the purpose of the "load equalizing hitch". Overload springs create the same effect. Factory overloads, should generally speaking, be removed.

Any truck scale will demonstrate those facts.

The purpose of the load equalizing hitch is to transfer weight. The addition of overload devices, progressively returns the weight to the coupler, which causes the sway.

The hook up rules are very simple.

1. The trailer should be level, when attached to the tow vehicle.

2. The tow vehicle should be level, when the trailer is attached.

3. The torsion bars must bend at least 3/4 to 1 inch. That effectively tells you that you have moved the tongue and/or trunk weight, correctly. A hitch bar rating too high, will not bend enough, but instead creates a harsh towing hookup ride.

The fall issue of "Airstream Life Magazine" starting on page 46, explains "towing mysteries".

Andy

Inland RV Center, In · 03-09-2005, 05:12 PM

Oooops.

For those that read the above post, I incorrectly wrote Trailer Life Magazine.

It has been corrected to read Airstream Life Magazine.

Sorry for any inconvenience.

Andy

markdoane · 03-09-2005, 05:52 PM

Where can I get a copy of the article, if I missed Airstream Life Magazine?

Inland RV Center, In · 03-09-2005, 06:19 PM

Subscribe to Airstream Life.

They have back issues available.

Andy

brunoffrance · 03-10-2005, 04:23 AM

The goal to install an air suspension or a Timbren kit, is to keep the level horizontally for the both vehicles, the Ford F150 and the A/S 27', without increase the work on the stabilizer chains. Even if there is an Harley, in the Pick-up bed, I don't think i overload the Ford when I tow .On the contrary, this system allows the stabilizers to work in good condition, with the hitch ball at the good level, and not too down if not.
I agree that to drive with an overload truck is unsafety but here it's not this situation.

Bruno.

Inland RV Center, In · 03-10-2005, 09:50 AM

brunoffrance.

I think your examination of the facts, is incomplete.

Take your rig to a truck scale, and report back to this group your rigs weights, with and without using the air bags.

Then that eliminates theories, but produces facts.

The purpose of "all" load equalizing hitches, is exactly that.

It corrects the tongue weight "AND" the excessive weight at the rear of the tow vehicle. The scales will prove that to you.

To artificially level the tow vehicle, in part defeats, the purpose of the hitch. Scales will prove that.

Automatic leveling on cars is the worst. Fortunately, people don't use cars as tow vehicles any more.

The scale tests were done hundreds of times, and proved the point "BEYOND A DOUBT" that adding any form of overload device to the rear end of any tow vihicle, will and does progressively, defeat the purpose of the load equalizing hitch.

The moral of the story.

Get truck scales readings, and then, analyze the hookup.

Anything short of that is pure "guess work," period.

Andy

brunoffrance · 03-10-2005, 11:58 AM

"Take your rig to a truck scale, and report back to this group your rigs weights, with and without using the air bags."

No need to go on a scale, the rig weight 'll not change with or without air bags so Timbren kit is only rubber "suspensions" , no compressor or heavy materials under the truck

"The purpose of "all" load equalizing hitches, is exactly that.

It corrects the tongue weight "AND" the excessive weight at the rear of the tow vehicle. The scales will prove that to you."

I agree but if you want to keep an horizontal rig you have to tender the 2 chains very hard when you load the truck because the rear is too much down, in spite of the new spings suspensions ; may be it's a factory choice to keep a comfortable truck on roads but not really in load situation.
I'have an European other truck, Ford too ( the first I used to tow ) and the rear was not so down so, no need to hard tender the chain to get an horizontal rig.

Andy, I'm not in an overloaded situation and i don't use air suspensions; The Timbren rubbers limits only the rear truck lowering ; Without that , really I think it'll be very dangerous to drive, because you 'ld touch the road with the rear truck or the tonghe when bad road coatings.

I've driven more than 2500 kilometers , last year and the F150 not overloaded but with an overloaded level is not really safety;I just want to correct that and not load until my F150 last limits...

Bruno;

Mike Lewis · 03-10-2005, 02:11 PM

Andy ---Think you're wasting your time with this fello...obvious he doesn't understand basic Geometry!!!!-------Pieman

Over59 · 03-10-2005, 03:55 PM

Question. Does the WD hitch move just the weight on the hitch or also the weight in the bed?
If the latter does this need to be considered in the size (lbs) bars one uses?
Since the WD hitch moves weight to the trailer axel as well, does it move some of the bed weight there as well.?

Inland RV Center, In · 03-10-2005, 05:31 PM

Over59.

A proper rated, properly installed load equalizing hitch, not only moves tongue weight, but it also moves trunk or bed weight.

Of the weight that is at the ball (tongue weight plus trunk weight), 60 percent goes to the tow vehicle and 40 percent goes to the trailer axle or axles.

That is why, as an example, when we used big cars as tow vehicles, we could have a very stable rig, when traveling, and a very unstable car, when not towing.

We I traveled the country with a 31 foot Airstream trailer, for Caravanner Insurance, I used a Buick Electra as a tow vehicle. The car was equipped with air shocks and air bags, with gauges for each on the dash.

The car by itself, with all the "stuff" I had to carry, was not very stable. Using both the air shocks and air bags allowed me to at least keep the car level.

When I attached the trailer, the air shocks went to the minimum 20 psi pressure and the air bags went to (if I remember correctly) 10 psi. The car also carried 65 gallons of fuel, plus tools etc.

Using a Reese 1000 pound full sway control hitch, allowed me to tow with two fingers on the steering wheel. I had absolute complete total control of the rig. When I had 65 gallons of fuel on board the car, I did have to use some air in the air shocks, but as I burned off the fuel, I would progressively drop that air pressure. Starting out, fully loaded, my torsion bars had a two inch bend in them. I had stability, big time.

But when I was using the car by itself, wow, another story. It was not very stable. Many times I had to travel to pick up one of our insureds trailer and take it to a dealer that could properly repair it. That's when the 65 gallons of fuel really paid off. I could go over 1000 miles, without the trailer, before I had to refuel.

Using a tow vehicle that has fixed overload springs may make the tow vehicle more stable, but it interferes with the load equalizing hitches ability, to do it's intended job.

Once again, opinions are opinions. But weight measurements made with specific criteria, are facts. These facts are also supported by the simple laws of physics.

It does not accomplish anything, by discussing these facts, "unless and until" someone had their five weights measured at a truck scale. Those weight readings will tell a person everything you want or need to know about load equaling hitches and how they work.

Those 5 weight readings are:

1. The tow vehicle front axle weight, without the trailer.
2. The tow vehilce rear axle weight, without the trailer.
3. The front axle weight of the tow vehicle, with the trailer attached.
4. The rear axle weight of the tow vehicle, with the trailer attached.
5. The trailer axle or axles weight while attached to the tow vehicle.

Additionally, if you really want to fine tune the rig, if you have a tandem axle trailer, while attached to the tow vehicle, weight just the trailer front axle weight, and then the trailers rear axle weight. Every truck scale may not be able to do the latter for you if the platform is very large.

With these weight readings, you can now change things around any which way you may choose, and see how quickly hundreds of pounds have been moved, perhaps properly, or improperly.

Once you get the weights out of the "envelope" you then greatly increase the likelyhood of a "loss of control accident".

Be safe, if not for you, but for your family and others.

Towing saftey, has no compromise. Anything short of the absolute maximum towing safety, is foolhardy, at best.

Yet people do it.

And so it is.

Andy

Jim & Susan · 03-10-2005, 06:34 PM

Bruno, I'm kinda new to all of this but I have some information you might find interesting. I have a 1997 Ford F 150 and a '73 Overlander. So we have similar rigs. The Ford owner's manual lists the following for tow weights and gross vehicle weights:

Engine-Axle Ratio-Max GCWR (KG/Lbs)-Max Trailer weight (KG/LBS)
4.6L----3.08-------4530/10,000----------2491/5500
4.6L----3.55-------5209/11,500----------3171/7000

GCWR is Gross Combined Weight Rating

My truck weighs about 4800 lbs (I have a camper shell on the back). The dry weight of trailer is about 4500 lbs.

All of this information can be found at WWW.FORD.COM Do a search on "towing" and look for a section called "heritage" information (at least I think that is what it's called). Older model vehicles don't appear in the tables with newer trucks.

I don't guaranty that this information is acurate, that's just what it says in the book.

Maybe this will help. It does look like you are close to your maximum weight before the Harley is even loaded in the bed of the truck. (I have no idea what the Harley weighs)

At any rate, hope it helps. Bon Chanc!

markdoane · 03-10-2005, 08:15 PM

Off the top, it sounds rather unlikely that you could fit a softail into the bed of a F-150. But if you could, the softail weighs 720#, the tongue weight is probably 600#, so the load would be 1320#. That's within the 1600# to 1800# rated capacity of a F-150, so maybe it's not unreasonable?

Of course maybe there's something in the "basic Geometry" that escapes me.

I agree that weights would tell the truth, but let's not ridicule the idea without the facts.

brunoffrance · 03-11-2005, 12:23 AM

Hi MIKE LEWIS;
May be you haven't understand that here it's a discussion forum and the purpose is to expose what you thinks right; It's what i do and Andy replies me. May be I don't understand what he tries to explain me and i try to reply correctly, with all i know when towing. Certainly Andy is right, it's a proffessionnal and me not, I'm only an A/S owner.
SO i don't authorise you do do this kind of invidious remark; If Andy wasted his time in replying me, it's not your thread and don't waste your time, you, in reply; You bring nothing concrete in this discussion and you'rent welcome Or tell me what to do to correct the level situation without using timbren kit.

thank you by advance for your advices.

fellow Bruno

nickcrowhurst · 03-12-2005, 05:17 PM

Bruno, Andy is absolutely right, in my humble opinion. I am a mathematics graduate, and I have also been a passenger in a trailer wreck when an improperly set-up trailer took us backwards through the hedge at the side of the highway. These two facts influence my approach to these matters. You are dealing with very serious issues here. Issues that can cause death. As Andy said, to understand what is going on, you just have to do the five weighings. The mathematics of weight distribution hitches is complex, but I wish to make a few basic points:
1. When you attach the trailer, the back of the tow vehicle goes down, but, crucially, the rear axle acts as a fulcrum, and the front of the tow vehicle goes up. The weight on the front wheels becomes less, so the steering forces available become less, just when you want them to be greater, with a heavy trailer to control.
2. The weight distribution bars should reload the front wheels to at least their load before the trailer was attached. You can check this by measuring the height of a tow vehicle front wheel arch before the trailer is attached, after the trailer is attached, and then as the chains are increasingly loaded.
3. If you change the rear suspension so that it is "harder", the rig can be made to "look right", but it will not necessarily "be right". The front end could still feel, and be, light. As Andy pointed out, the proposed changes could just disguise a dangerous set-up.
4. I would not use a tow vehicle so close to it's designed limits. The weighbridge is your true friend. You need to do the five weighings with all the people, food, water, tools, toys etc that you might one day carry. These are the facts from which you may start. Bear in mind that the manufacturer's load figures may not be unbiased by the need to compete with other manufacturers. I prefer to be at no more than about 75% of maximum rating. My trailer load is similar to yours, and I chose to buy a 3/4 ton truck, not a 1/2 ton. I would not use a 1/2 ton truck with that load. Many would be comfortable with a 1/2 ton truck with your rig, but I am just giving you the perspective of one who has been in a trailer wreck, and does not wish to repeat the experience. The fact that someone may have driven such a rig for 100,000 miles without incident is not the issue for me. I am concerned with the relative probabilities of a lack of control occurring when a rare combination of adverse factors coincide. For example, last month I was on I75 southbound near Tampa. There were roadworks on a bridge, and the highway narrowed right down and snaked through an s-bend, lined with those nasty concrete barriers. I slowed down. To my right I saw that there was a shallow ditch dug out of the road surface. I needed to move away from this ditch for safety, and , at that point, an 18 wheeler truck decided to charge through at over 70 mph. If I moved the steering wheel at all to the right we would have gone in the ditch. If I had moved to the left we would have hit the truck. There wasn't an inch to spare, and I knew the right tires were on the edge of the ditch, at about 50 mph. I froze, and the rig stayed rock solid, with no sway or sideways movement as the 18 wheeler blasted by, and there was no accident. That's why I have a long wheel base heavy truck that is nowhere near it's designed maximum load, with load distribution bars sufficiently tight to re-load the front steering wheels.
Bonne chance! Nick.