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DavidsonOverlander 02-09-2010 10:37 AM

What about receiver capacity?

Originally Posted by jmtandem (Post 805071)
I am sure a few of you have come to the same conslusion. After towing using diesel powered pickup trucks, I have concluded that weight distribution hitches really are not made for heavy front axle trucks. The diesel weighs so much more than a comparable gas engine that there is no reason to add more weight to that axle.

This makes a lot of sense to me, but I'm wondering about the capacity of the receiver. The receiver on my F-350 says 5000 pound trailer weight and 500 pound tongue weight without weight distribution. With wd it's 12500/1250. How much weight distribution would be needed to keep within the limits of the receiver?

bob34787 02-09-2010 10:49 AM

or if your dash lights are to bright " adjust the illumination intensity reostat"


Originally Posted by finalcutjoe (Post 804943)
This is so ridiculously vague, it's almost pointless.
How about: "Having an instantaneous deceleration with another object will make your journey less enjoyable."

jmtandem 02-09-2010 11:24 AM


You raise a very good point. My Dodge is rated sufficiently strong on the receiver without WD so not much of an issue for me. Many WD hitches (like HA) caution about not using them for 'off road'. I imagine that is to alleviate the tremendous stress encountered with road dips, irregular surfaces, etc. However, it you need WD to stay within the hitch ratings, then going off road with much more tongue weight is counterproductive and maybe will ovestress the receiver. Torklift and others make aftermarket receivers, some rated at 17,000 pounds. It might be worthwhile to investigate a stronger receiver.

ROBERT CROSS 02-09-2010 04:18 PM

The reason for weight distribution as I understand it is not to ADD weight to the steering axle.... but to REPLACE a portion of the weight that is removed when towing.

Our reciever...Reese Tow Beast Class V Receiver

2-1/2" Reciever tube opening

Weight Carrying: 1200/12,000 lbs.(TW/GTW)

Weight Distributing: 1700/14,000 lbs.(TW/GTW)

Road Ruler 02-09-2010 05:28 PM

My dad bought his 1st travel trailer in the late 50's. It was a 16' Shasta and the TV was a 1958 Ford Fairlane with a 6 automatic.

With the four of us, the trunk full, and trailer hooked up rear sag would have been outrageous without the use of the Equalizer brand, weight distributing hitch.

Since most TV's were cars back then it seems to me the idea was to distribute the weight, more or less to all four axles which it pretty much did in equal amounts, front/rear.

jmtandem 02-09-2010 06:58 PM

road ruler,

You dad likely did not use an Equalizer hitch in the late 1950's. Back then it was a dolly with a wheel on it that kept the trailer tongue at an acceptable height vis a vie the car or station wagon. But, your point was well taken- something was needed.

Road Ruler 02-09-2010 07:23 PM

I stand my my post. It was an Equalizer WDH. I recall how my dad complained about how poorly the car it felt when he tried "one extra link" on the torsion bar chains.

jmtandem 02-10-2010 08:53 AM

You have a good memory.

slowmover 02-10-2010 09:35 AM

For those contemplating not using a WDH, I recommend a reading of their owners manual: Mine -- from a 3/4T Dodge turbodiesel -- requires the use of a WDH when tongue weight is ONLY 350-lbs.

TW is not static as you run up and down the roadways. Unloading the front axle is flat . . . .

Okay, let me say it with civility. By lack of using WDH one lessens the braking and steering ability of the TV by failure to properly spread TW over all axles per a formula of leverage.

Under the best of circumstances, trailer towing doubles the risk of a loss-of-control accident. Is there a contradiction, there?


As to springs, yes, some are too stiff by design (not by capacity). Does that affect the trailer? Different question. A/S should provide some examples if they want to be believed (SAE?).

So far as I can tell (as of today) A/S decided to decrease aerodynamics, increase weight, and failed to provide a suitable frame/structure (whatever) for porky pig trailers. Maybe truck springs are a contributing factor, but they -- as a problem -- aren't the chief cause, it appears to me.

(I have yet to hear of anyone with separation problems on Silver Streak, Avion or Streamline; doesn't mean it hasn't happened, but I've looked everywhere I can online for any info on these brands and this has NOT been a topic of discussion among current owners of trailers AT LEAST twenty years old. If asked I'd have said A/S should have gone to preformed aluminum cabinetry per STREAMLINE -- riveted to walls & floors, increasing rigidity and reducing weight -- and, in this age of computers, applied some engineering to that frame; and had a modern look at aerodynamics. And fixed the filiform problem).

Road Ruler 02-10-2010 12:32 PM

1 Attachment(s)

Originally Posted by jmtandem (Post 807050)
You have a good memory.

Sometimes, but not always.

Even as a young teen I was into the whole car, trailer, towing thing. Back then folks did not know too much about the connections and the age of WDH's were just emerging. My dad had an RV dealership. From Ontaro we made many trips to Lapeer, Elkart, and Goshen picking up trailers. I think my dad liked towing them more than selling them.

Pic is from about 1963. Dad had a Mallard dealership.

Ag&Au 02-10-2010 04:55 PM


Originally Posted by Road Ruler (Post 807141)
Sometimes, but not always.

Even as a young teen I was into the whole car, trailer, towing thing. Back then folks did not know too much about the connections and the age of WDH's were just emerging. My dad had an RV dealership. From Ontaro we made many trips to Lapeer, Elkart, and Goshen picking up trailers. I think my dad liked towing them more than selling them.

Pic is from about 1963. Dad had a Mallard dealership.

From the company history: (Equal-i-zer® Hitch - About Us - Company History)

"1960 – The Equal-i-zer; Sales Corp. was developed as a division of Mobile Manufacturing. "

I would guess they were making hitches before then.

jmtandem 02-10-2010 05:56 PM


My Dodge manual for the '05 3500 devotes a whopping three pages to towing, over 30 to adjusting the radios and most of the rest of the 366 pages to air bags, seat belts and taking the truck to the dealer should it need attention. They don't get it. We buy one ton duallys to haul and tow, not to take the kids to the pre school, flower shop, etc.

My manual says the same as yours as it relates to Class III and IV hitches. It is silent about Class V hitches, and most that tow heavy use them. Also, there is little comfort in the tow section as it is almost contradictory . In one place is states that Class IV hitches are for a max rating of 1200 tongue and 12000 trailer weight. On the next page it states that the factory tow package includes a receiver that is rated to 12000 trailer weight and the tongue weight must be between 10 and 15%. Amazing, a Class IV hitch with a tongue weight that can go to 1800 pounds, I think not! It says nothing except what the max trailer can weigh. Lawyers wrote the section, all three pages about towing for a tow vechicle! I think it is better to use the towing guides, the receiver ratings for dead tongue weights and with WD. An 8000 pound trailer can be argued that it is maxing out the Class IV reciever as 15 percent tongue is 1200 pounds. For a tow and haul vehicle, maybe Dodge should let some of the lawyers actually tow with one and then write the section.

slowmover 02-11-2010 03:52 AM

Yes, jmtandem, I read that as meaning (deduction) that my 3/4T was limited to "about" a 10,000-lb trailer due to TW. The factory tow package hitch receiver isn't very impressive. But even with an aftermarket "beefier" hitch receiver, your point is well taken that a work related function is not at all clear or forthright in outlining the steps necessary to towing properly (however that should be defined). The lack of definitions anywhere we turn in re WDH's is aggravating as can be.

If the argument is that there are too many possible combinations used in too many possible ways (road, lack of road, etc, ad infinitum), then how about quoting relevant sections of SAE papers so we can at least look over the shoulder of those who test these things for their "ratings".

(I believe it was "markdoane" who provided this quote I copied unattributed):

*W. Korn, "Travel Trailer Design and Construction - How It Relates to Towability." SAE SP-259, January 1965

*R. Thomas Bundorf, "Directional Control Dynamics of Automobile-Travel Trailer Combinations" SAE Paper 670099, Jan. 1967

The Bundorf paper uses tire cornering stiffness and sideslip angles (for both the tow vehicle and the trailer) to calculate the yaw forces acting on the combination. These are used to describe the motion of the trailer and tow vehicle as a rotational inertia-spring-damper system, which leads to the frequency and damping equations.

From there he calculates the yaw velocity, sideslip angle, lateral acceleration, and towing angle responses.

What is really neat is that he can then change the tongue weight, TV rear overhang, tire stiffness, and 'centering force' (sway control), and determine the stability following a pertubation such as a passing truck.

And I am now waaay off topic, but it is the sort of information (endnotes, bibliography) that might put some usefulness into Owners Manual discussions. After all, testing has a beginning and an endpoint, and must work from particular definitions.

Or, in this quote off of

I worked at Ford's Arizona Proving Ground in Yucca, Az till they closed it last year. (2007 or 8). It was a truck/desert/durability-proving ground. When we did tow testing -- which was 10,000 miles -- we loaded a trailer to maximum GVW for that vehicle. Anything from a F450 to an Escape. The tongue weight was set at 10-12%. We had a stop and go course, and a high-speed 5-mile oval that we did on-site trailer towing upon, but about 80-90% of the 10K mile towing was on public highways.

On the public roads we drove to Bullhead City on Highway 68. BHC is at the bottom of a 12-mile-long, 6% grade. The driver left the proving grounds at the start of the 8-hour shift and drove the 60 miles to BHC, and for the next 5 hours he drove up & down the 12-mile 6% grade. We did that 24/7, 365-days per year. In the summer 125-degrees Farenheit is a routine temp along the Colorado River in this area. We did these tests with all our trucks, and all the competitor's trucks. We always tested at 100% GVW. Never 80%."

. . is about the only "argument" (entirely anecdotal, thus nearly worthless) about respecting GVWR, etc, and the falsity of the "80% rule".

Same for Airstream and warning against TV rear springs that are "too stiff" without (I assume) providing any guidance as to what that means, or how to calculate said problem. That a WDH sets up/affects a set/series of relationships is understandable and not open to bald pronouncements makes for difficulty, I'll grant. But the lack of basic perspective as given, undefined, by trailer and tow vehicle manufacturers is not acceptable per your example, and the original post of this thread.

Since the whole thing is about money (who is liable for repairs), it also seems moot. Another dead end.

jmtandem 02-11-2010 09:08 AM


In no way was I arguing with you. In fact my current trailer only weighs 8000 pounds. I got the truck to haul a 4000 pound cabover camper and still needed air bags and overload spring bumpers. If the truck's towing capacity is limited to the hitch, then it can tow more with a Class V hitch or a Fifth Wheel hitch. Their own analysis proves that out as they are rated higher with a fifth wheel hitch.

The more time I spend (many years since 1985) with cabover campers and lots of pleasant hours on the forums, I have learned that many, if not most, with cabovers are over some rating, usually the GVWR. I was not as I was more cautious about things like that. However, those that are ususally state their case as looking for the weakest link, tires, rims, axles, transmissions, brakes, engines, springs, etc. Often they respond to that weak link with aftermarket improved components and therefor are OK. Not being a lawyer, I think it would be arguable either way that if a deliberate progressive attempt to make the truck haul better was carefully undertaken, the truck could haul more. Look at the F 450, or the Dodge 4500 etc. and see what is really different compared to a 350 or 3500. Or a 2500 like you have compared to a 3500. What really makes a one ton that is not found in a three quarter ton? Same engine, transmission, tires, wheels, maybe a spring or two in the spring pack, maybe bigger brakes, etc. So, if you upgrade a three quarter ton to one ton components it should tow or haul like a one ton? I don't really know. But, do think a good lawyer could argue either way.

I am not aware of any accidents where anybody actually got the trailer weighed in relation to the truck. That could shed some light on this issue as it relates to the video you shared. I spend lots of time in the toyhauler section of the rv/net forums as they are as heavy as 18,000 pounds often towed by one tons and could find not one example of an accident where somebody was cited for being overweight. Maybe there are cases but I have not run into them. However, that being said, there is no safe way to tow more than should be towed and for the sake of family and others on the roads it should not be done. If Dodge really cared about how we tow, more than three of 366 pages in the manual would be devoted to the subject and it would not read like the same narrative covers minivans through medium duty trucks. And, of course, the max towing ratings are dependent on class of hitch as much or more than the rest of the truck. I apperciate what you said, always use a WD (now Equalizer 1200/1200) hitch and sway. I don't like to take chances. However, for my truck with the very heavy diesel engine all that I really need is sway as 1000 pounds on the hitch is only about 25% of the payloads capacity of the truck. Since my hitch cannot be used without WD to also get sway, I just go light on the bars to have sufficient tension for sway.

Good thread and good posts!

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