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Old 10-21-2010, 06:17 AM   #41 (permalink)
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Nice!!

But the website says *Available only in Canada

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Old 10-21-2010, 06:18 AM   #42 (permalink)
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I would get a trailer with all the front edges radiused, not just the top.
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Old 10-21-2010, 01:11 PM   #43 (permalink)
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Your family is worth how much? You have how much into van and trailer? A sway eliminating hitch is much less than 10% the value of the rig, isn't it? Maybe 5%?

Acutally, I don't know how much my family is worth. If I had to put a dollar value on that I guess we would stay home. Regardless, I did not realize they were that much $. Wow again! (and it's ~5% btw). It's interesting researching Hensley/ProPride history.

Some AS trailers are light. You are not weight-limited in the same way with an aero trailer if you'll educate yourself on the advantages. CAN AM RV in London, Ontario sets them up like was done in the 1960's. Understand that your van has not been subjected to proper testing, nor that the new J2807 standard is in any way realistic. Search for articles and posts by Andy Thomson of that firm. They've been doing this for forty years and have set of hundreds of your brand of van, and thousands of minivans to tow. Weight rating is relative to many factors. Reading will inform you of considerations.

And, yes, you can tow a heavier aero trailer than the ones shown here. You'll enjoy reading around on the subject.


There is a lot out there from him and it is interested reading. But I do believe I am weight limited for many reasons that have nothing to do with MPG. It might not be the 3500# that Toyota says as I am sure to be over that at some point. Let's say the TT added 0% to the aero drag, what's the weight limit for my TV? Can I tow 10,000#?

ON the trailer, start by having a big truck shop perfect TT axle alignment. If TT does not have shock absorbers, add MONROE Retrofit kit. CENTRAMATIC Tire Balancers are also good.

The Visa has a torsion axle. Do you think that's damping enough?

If the TT has cheap no-name tires I'd consider GOODYEAR MARATHON the default choice for ST tires.

They are bias ply. I have been wondering if a better tire would be worthwhile?
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Old 10-21-2010, 01:24 PM   #44 (permalink)
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"Once closed, the retractable roof creates an aerodynamic shape, which gives the Alto a drag ratio 75% lower that a traditional travel trailer."

BS again?
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Old 10-21-2010, 01:53 PM   #45 (permalink)
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Its neat how the expensive hitches give you the sway stability of a fifth wheel trailer. The propride and hennsley connect to the trailer with a a 4 bar trapazoid link. The converging links make the trailer move around a virtual pivot point near the rear axle. The Pullrite connects underneath the vehicle and has an actual pivot at the rear axle.
I've never heard of a hitch with trapezoidal links. That's pretty clever. Pic?
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Old 10-21-2010, 02:46 PM   #46 (permalink)
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I've never heard of a hitch with trapezoidal links. That's pretty clever. Pic?
The hensley and propride hitches have 4 bar converging links thats form a trapezoid shape with the small end of the trapezoid on the truck side and the big end on the trailer side. The way it rotates forces the trailer to pivot as if it was 5' forward at the axle.

I know trapezoidal link is a suspension term, not sure if its anything similar.

edit:

Last edited by miket; 10-21-2010 at 03:19 PM..
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Old 10-21-2010, 07:55 PM   #47 (permalink)
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The experience is as though TT and TV are locked together. The trailer literally cannot change direction, even minutely, until the rear axle of the TV moves. The price is cheap for this peace of mind. Used ones available if a Hensley Arrow (though not quite as good as a PP).
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Old 10-21-2010, 08:19 PM   #48 (permalink)
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It's interesting researching Hensley/ProPride history.


Best two threads on the Net are from the Airstream enthusiast site, Airforums


the ultimate haha users guide... - Airstream Forums

the unofficial pp users guide... - Airstream Forums

Now, whether you need one or not is up to you. The anti-sway works separately from the weight-distribution properties. A used Hensley can go for around $1200 or less on hitchtrader.com (or Craigslist) and you'd be pleased to have it. But it is more important to set up what you have properly in the first place, and that requires the use of a certified scale.


There is a lot out there from him and it is interested reading. But I do believe I am weight limited for many reasons that have nothing to do with MPG. It might not be the 3500# that Toyota says as I am sure to be over that at some point. Let's say the TT added 0% to the aero drag, what's the weight limit for my TV? Can I tow 10,000#?


You'd be surprised. TW is a limiting factor in my mind, but it's hard to argue with Thomson's approach and success. It's outside of standard ratings, but, frankly, they're not what they ought to be. We (self and others) who attempt to help others to set up their rigs default to manufacturer numbers. But it's not as if we didn't work with what worked, so to speak, in the 1960's and '70's. I think you can duplicate what CAN AM has done on a TV like yours with an otherwise identical trailer. But you need his hitch receiver (or plans) and need to follow his other guidelines (tires, shocks; speed of travel).

I've seen him set up Cooper Mini's and Jeep Wranglers to tow Airstream trailers much bigger than yours. You must do the homework and understand that some TT's won't work. It's all in the hitch rigging, and in TV prep. I look forward to getting up there some day and paying them to go over my rig.


The Visa has a torsion axle. Do you think that's damping enough?

Yes, independent suspension trumps all other kinds. Adding disc brakes is the worthwhile upgrade.


They are bias ply. I have been wondering if a better tire would be worthwhile?

A truck tire "LT" designation is the other choice. I used LT's on mine. Bias is a mistake. Put 'em on Craigslist. Tire rating and wheel rating must be appropriate for trailer. Cheap trailers have a habit of bieng shod with barely adequate suspensions, tires, brakes. Worth going through.

Some pics of your rig would be nice.

Here's an example of a newbie asking if his truck can tow a certain trailer. Note how the question is answered. This is the standard approach for a crude TV and even more crude TT:

EXAMPLE:

http://forums.woodalls.com/Index.cfm...d/24482184.cfm

I am new to this-hello. I am looking into buying a travel trailer. I have towed things like jet ski's, boats etc, but never a travel trailer. I am going to buy one this winter. I am having the hardest time finding one I like in the weight range I think I need to be within. My trucks specifics are this:

2009 Chevy Silverado 5.3 L 315 HP Z71 with the heavy duty tow package with all the coolers. Off road springs. Towing capacity of 9500-lbs.

I am getting all kinds of opinions of how much to be under my capacity. Here are the specs of the trailer. I have a friend that feels you should be 1000 pounds under your tow capacity in the end and it has me nervous. Again, I am rated for 9500 and wil have the weight distribution/anti-sway set up.

GVW: 9,250
Dry Weight: 7,480
Hitch Weight: 1,075

HELP.................

--------------------------------------

1] Load your truck approximately as it would be when ready for camping and get it weighed. This is your TV's GVW. Just for example, let's assume this turns out to be 6300#.

2] Find the manufacturer's Curb Weight for your truck. Let's assume this is 5300#.

3] Subtract the weight in [2] from the weight in [1]. For this example, the weight of "extras" (optional equipment, passengers, cargo, etc) which has been added to the base vehicle is 1000#.

4] Subtract the weight of "extras" (1000#) from the truck's "Maximum Trailer Weight" (MTW). For this example, the result is 9500-1000 = 8500#. This is the maximum that the TT can weigh when loaded for camping. It makes no difference if the TT's GVWR exceeds this amount as long as it is not loaded to more than the MTW minus the "extras".

5] Look on the truck's receiver for the "Weight Distributing" "Maximum Trailer Weight" rating. Use the smaller of this value or the value from [4].

6] Subtract the TT's GVW from its GVWR. Assuming your truck's GVWR is 7000#, the result for this example would be 7000-6300 = 700#. This is the maximum vertical load that your TT can exert on the receiver. The TT's tongue weight should be limited to about 115% of this value. For this example -- about 800#.

7] Look on the truck's receiver for the "Weight Distributing" "Tongue Weight" rating. Use the smaller of this value or the value from 6).

Now, for your candidate trailer --
GVW{R}: 9,250
Dry Weight: 7,480
{Dry} Hitch Weight: 1,075 (about 14% of Dry Weight)

Let's assume you can hold the loaded weight to 8500# (1020# above the Dry Weight). The resulting tongue weight might be around 1100-1200#.

Given the assumed weight of "extras", the tongue weight would be 300-400# over the allowable. This points out why it is very important to know the weight of the "camping-ready" truck as a basis for determining how much TT it can handle.

If the maximum allowable tongue weight does turn out to be 800#, that indicates the loaded weight of the TT probably should be limited to about 6400#. To handle the trailer you have chosen, the GVWR of the loaded truck would have to be around about 5900-6000#.

Ron Gratz

---------------------------------------------------------

The approach used by Thomson is different. An independently suspended, AWD vehicle is likely best, not a truck. The better handling the TV, then the better TV it will be while towing. Trucks are terrible for wrecks, etc.

And so on.

But you'll want to set yours up in the standard way, first, no matter the hitch brand. Of ordinary low performing anti-sway hitches the REESE Strait Line "Dual Cam" is the best. But it needs about 400# TW to operate properly.

What's the TW on those trailers?






.

Last edited by slowmover; 10-21-2010 at 08:43 PM..
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Old 10-21-2010, 08:49 PM   #49 (permalink)
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I would get a trailer with all the front edges radiused, not just the top.
ALL edges need to be radiused. Trailers exist in crosswinds, and many problems result from air not being able to slip over the trailer.

A heavy quartering crosswind is the hardest to deal with, especially gusting.

Some recommend installing an airspeed indicator just to be able to read what is happening.

All radiused edges -- on a trailer -- is more important than teardrop shape. A teardrop cargo trailer might be okay, but not in a TT being used for more than a 3-day trip. (See SILVER STREAK Clipper, above).

.

Last edited by slowmover; 10-21-2010 at 08:54 PM..
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Old 10-21-2010, 09:25 PM   #50 (permalink)
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I don't think any of the trailing edges benefit from radii, nor do the bottom edges but, yes, everything on the leading and top faces besides that rearmost edge.

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