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Old 06-27-2016, 10:21 PM   #1
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Las Vegas , Nevada
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First trip to CAT scales - NEED HELP

This is our second summer with our 19' International and we finally made a trip to the CAT scales on a trip a few weeks ago. I was loaded up more than usual as in addition to the AS I had three passengers and a load of cargo in the bed (moving son from his college home). So, I thought it would be a good time to check our weights and limits. After weighting in, I suspect our Equalizer WD hitch is not set up properly based on the results (despite paying Airstream of Orange County last year to adjust the hitch). Our TV is a 2015 F150 Lariat, max tow, 3.55 EB.

Here are the results of the weight in:

Truck & Trailer WITH weight distribution
front axle 3220
rear axle 3880
trailer axle 3980

Truck & Trailer WITHOUT weight distribution
front axle 3120
rear axle 4060
trailer axle 3920

Truck ONLY
front axle 3400
rear axle 3040

So, from what I can tell we were 80 lbs over the rear axle rating (3800), 50 lbs over the GVWR of 7050 and possibly even over the trailer GVWR of 4500 lbs (not sure if I am calculating this one correctly). Is it normal for the front axle to have LESS weight after attaching the trailer? My understanding is the trailer tongue weight should be spread across all three axles and, therefore, I should not experience weight loss on any axle. I have tried corresponding with the hitch manufacturer, but they have not been of much assistance.

I am doing my best to learn about all of these considerations, but it is a lot to digest when new to towing. I certainly want to keep my family and others on the road safe so I appreciate any perspective on my situation. Thx!
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Old 06-27-2016, 10:48 PM   #2
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2012 25' Flying Cloud
Battle Lake , Minnesota
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How To Set Up Your Equalizing Hitch
by Andy Thomson

Two of the great mysteries for trailer enthusiasts, whether they have towed for years or are just starting out, is how their equalizing hitch works and how to adjust it properly. I look at the set-up of every trailer I pass on the highway and it is rare that I find one that is connected with everything adjusted, as it should be. It is also not unusual to see combinations that have an equalizing hitch just resting on a ball.
Without an equalizing hitch we would not be able to tow trailers of any substantial weight. A trailer needs hitch weight to be stable and it is the action of distributing the weight over the entire tow vehicle that creates a bond between the trailer and vehicle. Even minor changes in the adjustment of the hitch can cause dramatic improvements in handling so it is well worth the effort to make sure it is correct. It is not rocket science so let me take you through it. The goal is to have the trailer riding level and the tow vehicle going straight down when the trailer is connected. By straight down I mean the front of the car will be pushed down from the weight of the trailer just as much as the back. This is not something you do every time you hook up just when you change tow vehicles or trailer or when you do something that substantially changes loading or if you make suspension changes such as new springs.
1) The first thing to check is that your ball is in as close to the back bumper as possible. If it can go in closer you should get an expert hitch installer to re-drill the 2" solid square section of the hitch and if necessary cut it to allow the ball to be as close as possible to the bumper. Even a couple of inches here will make a difference. At our dealership we use welded ball mounts whenever possible because they allow the ball to be closer to the bumper.

Try to have your rig loaded pretty similar to how it is when you normally travel. For better balance, if the water tank is in the front fill it, if it is in the back empty it. The only way to really adjust everything properly is to park the combination on a very flat surface, such as a concrete pad.
2) Park the unit in a straight line on the level pad.
3) Disconnect the trailer and move the tow vehicle forward 6". (Page Top)
4) Level the trailer: If the "A" Frame is level with the main frame rails then I usually measure to the bottom of the frame between the wheels and to the bottom of the "A" frame just behind the ball. Then measure from the ground to the top of the coupler to determine the ball height
5) Measure from the ground to the top of the ball on the tow vehicle - it should be equal to or 1/2" higher than the trailer ball height. This is especially critical if the trailer has independent suspension. If the trailer has leaf springs, the ball can be an inch or two lower. The weight between the front and rear axles is equalized on units with leaf springs.
6) Next check the angle on the ball mount. The ball mount should angle back as much as possible. This angle on the ball mount acts like the forks of a bicycle - it makes the unit want to stay in a straight ahead position (that is why you can ride a bike with no hands).
To check the angle, install a torsion bar in the ball mount and swing it parallel to the trailer frame. The end of the bar should be 4-5" off the ground when you lift it enough to take all the play out of it. If the ball height is over 22" then the bars can be a higher off the ground.
7) Back-up the tow vehicle so that the ball is under the coupler, but do not put any weight on the ball. Put some masking tape on each corner of the car and mark a convenient spot. Here we used 19". Now we know how the vehicle sits by itself.
8) We are now ready to start connecting the combination. Lower the trailer onto the ball and connect the torsion bars to the link that you think might be correct (likely the first or second link) and lower the weight onto the car. If you are connecting a vehicle with independent rear suspension do not raise the back of the car to connect the torsion bars, instead use a jack under the torsion bar if you need help to get the chain swung up.
9) Now measure the vehicle where you marked it and see how much it has been pushed down. It should go down evenly on all four corners. If it is down more at the back then you need more pressure on the torsion bars so you would reconnect using the next link. (Page Top)
10) Often you will hook up and the back will be down say 1 1/2" and the front will be up 1/2" but it you pull up the next link the back might be even and the front down 1" so you need something in between, you need a way to adjust a partial link. A 1/2" bolt pushed through two overlapping links is a 1/3 of a link of adjustment. So you can use one or two bolts in the chain to create 1/3 or 2/3 link of adjustment.
11) If the vehicle does not drop evenly side to side then you can put more pressure on one bar to compensate. The right hand torsion bar will affect the left front of the car and vice versa. Especially on pickup trucks due to the flex in the chassis the back end may twist in relation to the front. In this case the front is the most important.
12) If you cannot get the front of the vehicle pushed down no matter how far you do the bars up then the torsion bars are likely too light or the receiver on the vehicle is twisting and needs to be stronger.
13) Once you have everything set, mark the link you connect for future reference. We use a cable tie but a dab of paint or nail polish is a popular method. On a new hitch, the bars will work-in quite quickly and after a few hundred miles you may need to use a bolt to bring the bars up 1/3 of a link.
14) Install your sway control, breakaway cable, chains and lights, and you are ready to travel.
Once you know what the combination should feel like, you will notice when the hitch has worked-in further and the front wheels are not as firmly planted as they should be. I often will check and adjust the hitch as necessary when I stop for lunch or gas. Generally you notice the difference right away when you head back out onto the road.
I know this may seem complicated, but once you have gone through it a few times you will find hitch adjustment an easy and simple process. (Page Top)
*
Pasted from <http://www.rvlifemag.com/file313/hitchhints.html>
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Old 06-28-2016, 03:57 AM   #3
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2012 27' Flying Cloud
W , New England
Join Date: Oct 2012
Posts: 5,412
Quote:
Originally Posted by canyonduck View Post
This is our second summer with our 19' International and we finally made a trip to the CAT scales on a trip a few weeks ago. I was loaded up more than usual as in addition to the AS I had three passengers and a load of cargo in the bed (moving son from his college home). So, I thought it would be a good time to check our weights and limits. After weighting in, I suspect our Equalizer WD hitch is not set up properly based on the results (despite paying Airstream of Orange County last year to adjust the hitch). Our TV is a 2015 F150 Lariat, max tow, 3.55 EB.



Here are the results of the weight in:



Truck & Trailer WITH weight distribution

front axle 3220

rear axle 3880

trailer axle 3980



Truck & Trailer WITHOUT weight distribution

front axle 3120

rear axle 4060

trailer axle 3920



Truck ONLY

front axle 3400

rear axle 3040



So, from what I can tell we were 80 lbs over the rear axle rating (3800), 50 lbs over the GVWR of 7050 and possibly even over the trailer GVWR of 4500 lbs (not sure if I am calculating this one correctly). Is it normal for the front axle to have LESS weight after attaching the trailer? My understanding is the trailer tongue weight should be spread across all three axles and, therefore, I should not experience weight loss on any axle. I have tried corresponding with the hitch manufacturer, but they have not been of much assistance.



I am doing my best to learn about all of these considerations, but it is a lot to digest when new to towing. I certainly want to keep my family and others on the road safe so I appreciate any perspective on my situation. Thx!

It is a lot to digest but you're doing great so far! You're asking the right questions and you'll get a lot of help here. Search the forums for threads on this topic. Here's one I started to get the kind of insight you're looking for: http://www.airforums.com/forums/f464...es-105930.html

Lots of good insight there and that's just one example. Pay particular attention to the replies there from Ron Gratz - he's actually quite the expert on this stuff. You might want to post pics of your CAT scale tickets to get some real expert analysis. Mine (below) is probably directionally right but flawed at some level so take it with a huge grain of salt.

You ask if it's normal for the font axle to have LESS weight after attaching the trailer. The answer is YES - that's exactly what you should expect. Why? Because your truck is just sitting there minding its own business and all of a sudden you drop a bunch of weight on the rear bumper (I think 740# with your data but I could be wrong...). What happens there?

Well, that's going to push your rear end down and lift the front end of your truck up. This is exactly why you want a weight distributing hitch - to push (distribute) some of that weight off the rear axle of your truck on to both the front axle of your truck and the trailer axle.

And that's what happened!

When you put the trailer on (no WD applied), it pulled 280# off the front axle of your truck and pushed 1020# down on your rear axle.

When you applied WD, it started to have the effect you should expect - namely, you moved about 180# around off your rear axle and pushed100# back to the front axle (that's 100 out of the 280 you lifted off when you attached the trailer) and 60# back to the trailer axle.

Wait - that sounds like 100 and 60 shouldn't equal 180. That's due to the CAT scales measuring in 20# increments. So we're close enough for jazz here 😀

So now what?

Well, you look like you could use some more weight pushed to the front axle. You lifted 280# off and only put 100# back on. Your truck manual will tell you how much of that you need to restore - at least 50% (or 140# in this case) and possibly a full 100% or 280#. Either way, you need to apply more WD.

So I'm not sure how you do that with your particular hitch - probably adding another link or two (I use a different style hitch with screw jacks to control WD). And when you apply more WD, you're not only going to move more to the front axle of your truck, but you're also going to take more off your rear axle and put it on your trailer axle.

Those are some of the basics and in my non-expert opinion, you're doing great! Moving in the right direction. Just some tweaks to make. But one big question for you...

When you did this weigh in, were you, the 3 passengers and "college gear" all in the truck for all 3 weight tickets?

If so, that's more than you'll be carrying for camping so you don't really know if you're overloaded in real life.

You're close, so another set of weight tickets, truly loaded for camping (if it's just the 2 of you, just go with the 2 of you, have a full tank of gas, whatever gear you'd normally bring, full propane tanks, camper full of your dishes, clothes, etc.) and then with more WD applied you will know the full story.

You'll also be able to calculate whether you're within tolerance on your truck's cargo capacity. But start with that new set of real world weights, apply more WD, post pics of the tickets and you'll get some better advice from people who really know what they're talking about 😀

You'll get there!! Keep asking questions!!
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