Bucking Bronco

[BillTex]

Originally Posted by safari 28

The hitch is needed because according to Inland Andy most who have a 3/4 ton do not need it for most of the Airstream line. He calls it overrigging. He feels a 1/2 ton is just perfect, and 2 wheel drive is better than 4 wd due to the ability of the weight distribution system being able to transfer weight to the front of the truck.

Try this on your 3/4 ton. Hook up the rig and jump on the rear bumper. I weigh 190 lbs. If you do not feel at least 2- 3 inches of travel then you are putting stress on your castle. Andy says it causes lots of problems from rivets popping to all kinds of interior stress and damage. 1/2 tons set up correctly will have the travel needed and I can feel her giving constantly on bumps. Someone mentioned it is used by horse trailer applications as the 3/4 tons were causing broken legs or some injury / a real problem on fivers as well and they have air hitches on the 5th wheel.

Wow-3/4 tons must be the cause of a failing economy, the war in Iraq, and the mortgage crisis too!

[safari 28]

Originally Posted by BillTex

Wow-3/4 tons must be the cause of a failing economy, the war in Iraq, and the mortgage crisis too!

That was an interesting response??

[Airstreamer67]

Safari28, I think your description is right, as observed by Andy.

I know I have too much truck for a 6000-pound trailer, but I wanted the power (215hp, 425ft-lbs torque) back in 1996 when I bought my 7.3-liter Navistar F250 diesel. Nowadays, the horsepower and torque of the new diesels is way over what I have, which is actually overkill for my application. So, if I were buying a new pickup for my trailer today, I probably would buy a V8 or V10 gasser on a half-ton chassis.

However, I'm not going to do that, because I still have too many miles left in my old diesel, and it is also quite economical to operate without all the new emission control equipment (15.5 mpg towing average on my 2000-mile trip last month to and from Big Bend in Texas' hill country).

So, three years ago I invested almost $1K in the AirSafe air hitch to treat my trailer better and keep it rolling past the repair shops without stopping. It has proven to be a very good investment.

[BillTex]

Originally Posted by safari 28

That was an interesting response??

This “theory” of stiff TV suspension abusing your AS has been around for some time. It completely negates the fact that there is a very compliant suspension system under your AS.
Assuming you have suspension under your AS, in working order, I cannot understand how TV suspension will affect your camper.
I suppose one could perform test drives with accelerometers mounted throughout your AS to measure frequency (Hz) and amplitude of vibration over the same road course and this may prove/disprove this “theory.” Until someone does this experiment, I don’t buy it.
It appears to me, after my experience, that a ½ ton suspension is overloaded once you get to ~ 1000# tongue weight, a few passengers, etc and that a ¾ ton suspension is nicely compliant at those loads.
If someone can explain the thinking behind the “overloaded suspension is good suspension” theory I would be more than willing to consider it.

When placing a load at an extreme point on the TV (hitch ball) the vehicle inherently becomes unstable if that load is excessive; the opposite end –steering axle-will begin to lose friction contact with the road, resulting in a loss of steering. The load should be distributed evenly between TV axles to maintain steering. Steering, braking, and safety are the first priorities. Any load transferred unduly to the frame of the camper is a secondary concern. If I cannot steer my truck because I have not distributed the load on my axles appropriately, and kill myself because of that loss of steering, I really won’t be concerned with the amount of force transferred to the trailer “A” frame.

The window of safe operation related to suspension is larger relative to the difference between TV rating and the size/weight of the trailer. This window (margin of error) becomes much smaller when the TV approaches its maximum capacity. I could drop my camper right on my hitch with no WD and be within the stated ratings for my TV (would this be the extreme example of “pampering” your “A” frame?).

FWIW, AirStream has no record of “A” frame failures due to stiff suspension.

It is not typical, nor do I think practical, to advocate that someone purchase equipment rated for less than its intended duty. In the unfortunate event of an accident, I am not sure how the authorities, and insurance investigators, would interpret that either.

Disclaimer; this is not intended for those that use airride, I am sure it is a good product. I just don't understand this whole "stiff suspesnion=bad suspension" debate.


Bill

[safari 28]

I yield to Inland Andy to support his theory. I do know I am well within the guidelines of the trucks capacity. I have no liability issues. Things have changed for 1/2 tons in the past few years, indeed, with numbers being blurred between 1/2 and 3/4 ton gassers. Please remember we are towing, not hauling. Despite this, time will tell if Inland Andy and other RV service outlets are laughing all the way to the bank because of all the overrigging he claims doing accelerated damage to the coach. I know if I had a 3/4, this air hitch would be on my radar.

[BillTex]

Originally Posted by safari 28

I yield to Inland Andy to support his theory. I do know I am well within the guidelines of the trucks capacity. I have no liability issues. Things have changed for 1/2 tons in the past few years, indeed, with numbers being blurred between 1/2 and 3/4 ton gassers. Please remember we are towing, not hauling. Despite this, time will tell if Inland Andy and other RV service outlets are laughing all the way to the bank because of all the overrigging he claims doing accelerated damage to the coach. I know if I had a 3/4, this air hitch would be on my radar.

I am not so sure it is Andy's theory-although he does support it. Andy is very knowledgeable, and has helped me personaly several times. A generous person indeed...
I don't subscribe to this theory though (where ever it originated)...

Your 1/2 ton truck still has a payload of ~ 1600# ( mythical "tow ratings" are only one number we have to watch; GVWR, GAWR are others). I don't know what your TW is, and I wasn't singling you out. I do suspect however, that with a 28' unit, it's comensurate TW, some passengers, etc that you are most likely over your rated payload capacity, maybe GAWR also. This is the issue with 1/2 tons towing 25' or greater (not "tow ratings"). A trip to the scales will yield the whole story.
I don't know that any of us are smart enough to deduce that a particular truck makes rivets pop out. There are way too many variables that could contribute to this phenomena. Our 20 yr old unit is still rock solid (one of the reasons we bought an AS!). The PO towed with a 3/4 ton Burb, we tow with a 3/4 ton also.
I am still waiting to find popped rivets.

We all have a responsibility to ensure our rigs are safe as can be before we hit the highways.
Being within rated (legal?) capacities is a good way to start.

Alas, we are way off topic...

Bill

[HiHoAgRV]

Originally Posted by BillTex

...I suppose one could perform test drives with accelerometers mounted throughout your AS to measure frequency (Hz) and amplitude of vibration over the same road course and this may prove/disprove this “theory.”...Bill

Thats exactly what I'm doing in the "epiphany gets new axles" thread...if I ever get my new-new axles
At least I have the "before" data posted...

[BillTex]

Originally Posted by HiHoAgRV

Thats exactly what I'm doing in the "epiphany gets new axles" thread...if I ever get my new-new axles
At least I have the "before" data posted...

My point exactly; if your suspension is functioning (and it may not be!) then what you tow with should have little effect on how the AS "rides"...

Good luck with Epiphany!

Bill

[HiHoAgRV]

Originally Posted by BillTex

My point exactly; if your suspension is functioning (and it may not be!) then what you tow with should have little effect on how the AS "rides"...

Good luck with Epiphany!

Bill

I hope to have time to be able to measure the ride in the front of the trailer as well as over the axle. I suspect the front of the trailer will have the same ride as the truck since they are firmly tied together. My question is with only a few inches of travel, does the rubber suspension really ride any better than my firm 3/4 ton. That is the reason I did the first data collection directly over the trailers suspension, that's as isolated from the truck as I can get. The first runs do show a difference between the center of the truck and the axle of the trailer. Thus I suspect the front of the shell to have the same ride as the truck (better or worse...)

[whatsnext]

Originally Posted by safari 28

The hitch is needed because according to Inland Andy most who have a 3/4 ton do not need it for most of the Airstream line. He calls it overrigging. He feels a 1/2 ton is just perfect, and 2 wheel drive is better than 4 wd due to the ability of the weight distribution system being able to transfer weight to the front of the truck.

Try this on your 3/4 ton. Hook up the rig and jump on the rear bumper. I weigh 190 lbs. If you do not feel at least 2- 3 inches of travel then you are putting stress on your castle. Andy says it causes lots of problems from rivets popping to all kinds of interior stress and damage. 1/2 tons set up correctly will have the travel needed and I can feel her giving constantly on bumps. Someone mentioned it is used by horse trailer applications as the 3/4 tons were causing broken legs or some injury / a real problem on fivers as well and they have air hitches on the 5th wheel.

I agree with this statement very much. I have also driven around Oklahoma City and on I-90 up north. I tow a 30' SOB weighting about 7000lbs with a 3/4 ton Suburban with an 8.1 engine. This means that my Suburban has Autoride suspension with a added price of $1,500. This is a direct quote of the owner's manual description on how Autoride works. Don't confuse this with the auto leveling system from a 1/2 ton Suburban. This Autoride system essentially turns shocks off electrically when not needed and instantly turns them back on when the sensors/computer thinks they are needed. I don't want to imply that tow/haul will turn them completely off or on while travel on a bumpy road, but it does change the parameters of the suspension notability.
The Autoride feature will provide a superior vehicle ride and handling under a variety of passenger and loading conditions.
The system is fully automatic and uses a computer controller to continuously monitor vehicle speed, wheel to body position, lift/dive and steering position of the vehicle. The controller then sends signals to each shock absorber to independently adjust the damping level to provide the optimum vehicle ride.

Autoride also interacts with the tow/haul switch that, when engaged, will provide additional control of the shock absorbers. This additional control results in better ride and handling characteristics when the vehicle is loaded or towing a trailer.

I found that while traveling these rough roads I can turn tow/haul off, and lessen the bounce and porposing. In other words, making the suspension more compliant (loose) helps somewhat. I turn tow/haul back on... less compliant (tight/stiff) and it gets worse. I can do this at any speed and the results are always the same. So yes, I do believe that stiff sprung TVs can cause harm to an Airstream or any other rig. This makes a case for that airsafe hitch. No, I have never tried one, but might sometimes. I also do not think that one can completely get rid of this problem, because it a combination of tow vehicle, trailer, road, balance, timing, and equal length segmenting of the road sections.
Other factors that help.

• Lessen the amount of weigh transfer by backing off the bars a link. This allows the front of the TV to absorb a little more of the bump. I tried to tighten the bars and the bounce became much worse.
• Slow down as much as you can and still be safe.
• If you can transfer a little weight off the tongue might help. Maybe add or remove water in a tank.
• Find a better lane or road.
• Try an Airsafe hitch if you have the money.
• Turn off your tow/haul until the road is smoother. This works only on 3/4 ton Suburbans with Autoride.

Sometime if I get the time, I might replace the bottom leaf (the heavy overload leaf) with a standard leaf and see what happens.

[SteveH]

Originally Posted by BillTex

My point exactly; if your suspension is functioning (and it may not be!) then what you tow with should have little effect on how the AS "rides"...

Good luck with Epiphany!

Bill

Bill,

As I see and uderstand it, it's not the trailer suspension that is the problem, but the very stiff rear suspension of the tow vehicle that is shocking the front of the trailer as it hits significant bumps in the road.