First weigh of truck and AS

[out of sight]

Scroll up. I gave you the tongue weight number. 980 lbs.

[out of sight]

Originally Posted by SteveSueMac

Again. For the love of camping - POST THE TICKETS!!!!


Your last set of numbers says you have an 1800# tongue. Post the tickets. Describe your process. Then we can unpack what you’re seeing.

And for comparison’s sake - my 980# tongue lifts 460-480# off the steer axle of my 3/4T diesel truck. Different brand than yours yes - but that’s quite a difference. Post the tickets. Describe your process. Then we can actually talk.

Why is this so difficult??

Frankly, I find it annoying that when I give you all the numbers on the tickets you don't believe them. In effect, you're calling me a liar.

[SteveSueMac]

OOS - You’re either unwilling or unable to listen to what I’m saying.

Your posts on this are confusing and contradictory. Still lacking actual tickets, one data set suggests an 1800# tongue weight, another states 980#, but you get to the 1800 by adding cargo, which suggests you may have done the process differently than I understand how it should be done - which doesn’t make me or you right or wrong - nor does it make you a liar - it means we don’t have a common language for the scenario. How can I make that clearer to you?

I’m not calling you a liar. I’m saying - for the last time - I don’t UNDERSTAND how you’re getting to these numbers.

You haven’t shown the tickets. You haven’t described the process you used to get the weights. You haven’t addressed whether it was the same day, the same loads; you said earlier the scale tickets matched your calculations but you haven’t said what those were or whether you calculated something first then went to the scales, or the reverse. Either way you’re not sharing the tickets or explaining your process. I can’t call you a liar - I don’t understand what you’re saying to evaluate whether it’s credible or not!

Post. The. Tickets.

Describe. Your. Process.

If you’re up for that - I look forward to talking with you about it and maybe we can both learn from each other.

If you honestly do not comprehend what I’m suggesting here, please tell me what needs clarification.

If it’s anything else - I’m hard pressed to understand how I’m not being trolled for sport. If that’s NOT your intention - please humor me - and - well, you know......

[out of sight]

Let me summarize. I have two scale tickets:

1. empty truck, no trailer, no cargo no passengers, full tank
steer 4760
drive 3240
total 8000

2. truck with trailer, loaded for camping
steer 4680
drive 5120
total 9800
trailer axle 6220

I also have a tongue weight scale that shows 980 lbs when loaded as above.

My premise is that, when loaded as in 2., the truck is near perfectly balanced and it does not need a weight distribution hitch, and it does not need a sway control device because it does not sway.

[jcl]

Originally Posted by out of sight

The front axle only has 80 lbs lifted off due to the 980 tongue weight. One of the reasons for that is that by towing on the ball the distance to the axle, and the leverage, is minimized. A wd hitch can add a foot to that distance and the leverage is increased. Also by increasing that distance the sway stability worsens.

Agreed on the distance to the hitch ball, but sway isn't worsened, the propensity to sway is, but that propensity is also reduced by the WD and anti sway hitch itself, so the net result is a gain, not a loss.

Originally Posted by jcl

You continue to ignore the contribution of the distance from the TV rear axle to the hitch in terms of contributing to instability and sway. It has been pointed out before.

The TV rear tires you are relying on to resist lateral forces are not located where the lateral loads on the hitch are applied. That lever is what contributes to sway. If you want the rear tires of the TV to resist lateral forces you need to move to a 5th wheel trailer. Or use a 3P hitch.

Originally Posted by out of sight

Scroll up. I did mention the distance to the axle, and how a wd hitch increases it, contributing to sway.

You mentioned it, but conveniently ignored that a WD hitch doesn't increase it from zero, it increases it from 4 feet or whatever the distance is from the rear axle centreline to the hitch ball. You are pretending the distance doesn't have an impact, by suggesting that the rear tires can control trailer sway and resist any lateral force exerted at the hitch ball by the swaying trailer. They call this being hoisted by your own petard.

You continue to refer to truck sway (something that the truck tires can resist) while not addressing trailer sway. The sway originates from the trailer, not the truck. If you want your truck to control a pivoting around the hitch ball you need to have something other than a pinned joint to accomplish that.

[SteveSueMac]

Originally Posted by out of sight

Let me summarize. I have two scale tickets:



1. empty truck, no trailer, no cargo no passengers, full tank

steer 4760

drive 3240

total 8000



2. truck with trailer, loaded for camping

steer 4680

drive 5120

total 9800

trailer axle 6220



I also have a tongue weight scale that shows 980 lbs when loaded as above.



My premise is that, when loaded as in 2., the truck is near perfectly balanced and it does not need a weight distribution hitch, and it does not need a sway control device because it does not sway.

Ah! Good! Now we’re getting somewhere even without the tickets! Ready? [emoji3]

Ok - let’s start by asserting there is not necessarily a right or wrong way to weigh the rig - but it’s clear you and I go about this very differently which may explain why I couldn’t understand your numbers - not calling you a liar - but literally couldn’t understand what you were saying. Why?

Well, I use the 3-pass method described on the CAT scale site - I get that you don’t use WD so one of those steps wouldn’t apply to you. The two that we both use but do VERY differently are done for me on the same day (usually within minutes of one another) with the same exact loads.

My process - not a right or wrong process; just the one I follow - starts with having the rig fully loaded for camping - full fuel, full propane, full load of unnecessary camping gear in the truck bed, full fresh tank, dishes, clothes, shoes, full fridge, DVD collection, pots and pans - everything we take with us in the trailer for camping.

I get my 3 weights *in reverse order* because it’s a time-saver - you wouldn’t use the first one - but with the fully loaded rig, I get to the scales and:

1) weigh the rig (steer, drive, trailer axles) with my WD applied where I think it should be based on last year’s weights (usually 5-6” on the jacks of my ProPride) - again, you wouldn’t do that step - but that set of weights is my first ticket and demonstrates what the WD hitch has done to move the impact of attaching the trailer to 3 sets of axles (once compared with the next 2 weights)

2) I get off the scales, circle back around, and before getting back on the scales, I remove all WD by dialing down the ProPride jacks so they hang loosely like I’m about to unhitch. They’re moving no weight anywhere in that position (other hitches do it however they work). This ticket will tell me what happened to the steer and drive axles on my truck when the trailer got connected (when compared to the next one).

3) I get off the scales and unhitch the trailer completely. I spin back to the scales and now weigh the truck by itself.

In my process - I’ve got an apples to apples comparison between the truck by itself fully loaded for camping (the 3rd step mentioned above) and what happens when that same exact truck with the same exact stuff in it gets connected to the trailer without any WD applied (the second step mentioned above).

That’s as far as you’d go in your measures.

The difference is - in your process, you have a non-camping-ready truck weighed let’s say on a Monday - and then you load the truck with all your camping stuff and go back with your loaded trailer on say a Tuesday and end up essentially comparing apples and fetzer valves.

I’m not aware of a way to discern from your process what is actually happening to your truck’s axles by connecting the trailer because your process introduced a ton (maybe a half ton) of variables that cloud the picture. That’s why it appeared to me you had an 1800# tongue! You went from a solo truck of 8000# to a hitched truck weighing 9800#! You later said your tongue was 980# but that’s not what your tickets were saying - at least not if done with the process I described. We could assume the value in your process is that you can estimate cargo consumption because your numbers get the difference in truck weight and you measure the tongue on a (Sherline?) scale separately. However - I believe your process introduces too many x-factors to show what’s really happening to your axles.

I could easily be wrong here but I think to actually see what’s happening to the weights on your truck axles, you may want to try the process I use and described above. I’d be glad to reimburse the cost of your two passes at a CAT scale if you want to try it using that process as an investment in a scientific experiment!

You also say that you find the weights in your measurement 2 above to be balanced. I believe you’ve said that’s because those weights are both 78-79% of their respective GAWR. If that works for you, it works for you. On my tickets, that first one I measured in the process I described - with WD applied - has the steer and drive axles of my truck each at exactly the same weight (and they were far out of balance in both of the other measures for the record). I’ve posted several sets of tickets many times but my summary from the start of this camping year would be:

Max steer: 5200
Max drive: 6200

Truck solo loaded for camping:
St 4660# = 89.6% (% of GAWR)
Dr 3340 53.9%

Add trailer with no WD
St 4200 80.1%
Dr 4840 78.1%

Apply just under 6” WD on ProPride
St 4480 86.1%
Dr 4480 72.2%

Thanks for explaining your process - I now get the disconnect. That was easy! [emoji3]

[out of sight]

A train is moving down the tracks pulling a car with a loose, freely pivoting coupler. A wind comes along and gives the car a propensity to sway, but it can't sway because the wheels are trapped by the tracks, just as if you were pulling it with a truck with very high (infinite) tire friction. No sway device is required.

[jcl]

Originally Posted by out of sight

A train is moving down the tracks pulling a car with a loose, freely pivoting coupler. A wind comes along and gives the car a propensity to sway, but it can't sway because the wheels are trapped by the tracks, just as if you were pulling it with a truck with very high (infinite) tire friction. No sway device is required.

Oh dear, that is a very unfortunate analogy. Your train has wheels at both ends, mounted on bogies, it doesn't just have an axle or axles in the middle of the train car. It is the two sets of wheels that stops it swaying, and they are spaced far apart.

Your Airstream has axles in the centre (slightly behind centre, but you get the point). It can pivot freely at the front connection. Thus it can sway. The resistance to sway at the coupler is not applied at the TV rear tires (which you claim have infinite friction). If you want to rely on the rear tires of the tow vehicle, look to a 5th wheel trailer, because that is where the pin is on that design, over the rear tires of the tow vehicle.

All trailers move back a forth a little, it is the nature of the beast. It is the feedback loop set up when the trailer starts to move sideways, the resultant lateral force is applied to the hitch ball, that causes the tow vehicle to turn in the opposite direction to the trailer sway, a correction brings it back but causes the trailer to accelerate in the opposite direction, and now you have an unstable system. Tow vehicle tire friction isn't an issue.

[out of sight]

If you have a hitch to adjust then the 3 pass system is what you need. I have nothing to adjust. I weigh it only once to see if my calculations are in the ball park and that's it. I may want to make some minor load distribution adjustments in the trailer and truck bed but that can be done with a hathroom scale and a tape measure.

If you buy a new tow vehicle you should try to figure out your axle loads before you buy. Thats what I did and it seems to have worked out quite well. The biggest problem is to determine the axle base weights. RAM publishes these but Ford does not.

[out of sight]

All I can say is you would be much better served if instead of spending the money for a Hensley you upgraded your tow vehicle and towed on the ball. Try it. If you don't like it you can always buy a hitch.

For those who are afraid to tow on the ball, dont forget, you always have ESC to bail you out. I've never had it activate on me but from what I've read it really works in a catastrophic event such as when you are already in an accident.

[SteveSueMac]

Originally Posted by out of sight

If you have a hitch to adjust then the 3 pass system is what you need. I have nothing to adjust. I weigh it only once to see if my calculations are in the ball park and that's it.

...

Wow.

SMDH.

Peace out.

[DewTheDew]

Originally Posted by SteveSueMac

Well, I use the 3-pass method described on the CAT scale site - I get that you don’t use WD so one of those steps wouldn’t apply to you. The two that we both use but do VERY differently are done for me on the same day (usually within minutes of one another) with the same exact loads.


I get my 3 weights *in reverse order* because it’s a time-saver - you wouldn’t use the first one - but with the fully loaded rig, I get to the scales and:

1) weigh the rig (steer, drive, trailer axles) with my WD applied where I think it should be based on last year’s weights (usually 5-6” on the jacks of my ProPride) - again, you wouldn’t do that step - but that set of weights is my first ticket and demonstrates what the WD hitch has done to move the impact of attaching the trailer to 3 sets of axles (once compared with the next 2 weights)

2) I get off the scales, circle back around, and before getting back on the scales, I remove all WD by dialing down the ProPride jacks so they hang loosely like I’m about to unhitch. They’re moving no weight anywhere in that position (other hitches do it however they work). This ticket will tell me what happened to the steer and drive axles on my truck when the trailer got connected (when compared to the next one).

3) I get off the scales and unhitch the trailer completely. I spin back to the scales and now weigh the truck by itself.

I am curious why you pull off the scale (twice!). When I did it (I am the original poster) I had the steer wheels on one pad, the drive wheels on the second, and both axles of the AS on the third. For the second weighing I just dropped the front jack on the AS, took off my Equalizer bars (leaving the trailer hitched and the big coupler in place), pulled the jack back up and weighed it again (equivalent to your second step). Then I just backed the trailer up until the front jack would be also on that third pad, dropped it and unhitched, then pulled back up a couple of feet to weigh the truck (and also weigh the complete trailer). After that I just backed up the truck a bit and re-hitched.

So I am wondering why you are pulling around, or why you do not leave the trailer on the third pad and weigh it by itself. Just curious; this was the first time I actually did this. I was happy no one was behind me waiting; I hate pressure!!! Still, it went fairly quickly; seven minutes from the first weight to the third.

On another note, now I'm looking at an F250...... :-)

[SteveSueMac]

Originally Posted by DewTheDew

I am curious why you pull off the scale (twice!). When I did it (I am the original poster) I had the steer wheels on one pad, the drive wheels on the second, and both axles of the AS on the third. For the second weighing I just dropped the front jack on the AS, took off my Equalizer bars (leaving the trailer hitched and the big coupler in place), pulled the jack back up and weighed it again (equivalent to your second step). Then I just backed the trailer up until the front jack would be also on that third pad, dropped it and unhitched, then pulled back up a couple of feet to weigh the truck (and also weigh the complete trailer). After that I just backed up the truck a bit and re-hitched.



So I am wondering why you are pulling around, or why you do not leave the trailer on the third pad and weigh it by itself. Just curious; this was the first time I actually did this. I was happy no one was behind me waiting; I hate pressure!!! Still, it went fairly quickly; seven minutes from the first weight to the third.



On another note, now I'm looking at an F250...... :-)

Hello OP - thanks for reading the book I wrote in that reply [emoji3]

Your process sounds fine to me. I think I chose to circle around twice to not be a nuisance to anyone behind me, especially professional truckers. The first time I did this I was literally up the whole night before going over the process in my mind to not get in anyone’s way.

Good luck!!

[Profxd]

Wow is right! I believe it was JCL that said sway originates in the trailer and he is 100% correct. Weight distribution, axle position, yaw inertia, and it’s effective tongue length are critical trailer data points. Sway forces are dampened primarily by the trailer and TV rear tire forces (cornering stiffness). The tires ability to resist these forces will diminish with reduced weight and forward velocity. The addition of tongue weight and WD reduce TV handling which is a different issue all together.

[twbucksr]

Out of Sight,

There are plenty of YouTube videos showing travel trailer accidents resulting from sway.

Fun to watch.

After watching a few, I hope they change your mind regarding your statement “and because I have the full tongue weight on the rear axle the trailer doesn’t sway and no sway control device is required”

[out of sight]

These videos of swaying trailers are all the result of back-end loading of the trailer. Every trailer will sway at a certain speed if the center of gravity of the trailer is too far back. A typical new Airstream with 10 to 15% hitch weight will never sway at normal highway speeds and you have nothing to worry about. If you have 0 to 5% tongue weight, however, you will reach critical speed very soon and your trailer will sway.

These videos are often used by people who sell sway control devices to needlessly frighten their potential customers into buying. It's a deplorable sales technique but it seems to work on many people.

[Westfork]

Out of sight. I tow on the ball and I gotta tell ya you are never going to convince the WD folks otherwise. They may have valid points and have taken a lot of time to reply and give feedback. I’m thankful that we have so many opinions and insights that allow us to make a decision on what works for our particular combo.

All that said nothing replaces a properly loaded trailer and tow vehicle combination. Truth is some trailer and rig combos just don’t need WD. Yet other combos most definitely need WD.

I’m on the fence about sway control too. If you have a good TV and trailer combo and keep the speeds down I’m not sure that is necessary either. It couldn’t hurt but it’s not always necessary. There are sway only options out there like Hayes or friction for sway only and no WD.

Next thing you know people are gonna tell me I need WD to tow my 22 sport with my 2019 3500 HD dually Chevrolet Duramax.

[out of sight]

There actually are people here who would say you need a w/d and sway control hitch to tow a 22 with a 3500. I've seen them.

[SteveSueMac]

Originally Posted by Westfork

...snip...

I’m on the fence about sway control too. If you have a good TV and trailer combo and keep the speeds down I’m not sure that is necessary either. It couldn’t hurt but it’s not always necessary. There are sway only options out there like Hayes or friction for sway only and no WD.

Next thing you know people are gonna tell me I need WD to tow my 22 sport with my 2019 3500 HD dually Chevrolet Duramax.

I can’t imagine a 22 would lift much off the front end of a diesel 3500. My 27FB lifts 480# off the steer axle of my 2013 Chevy Duramax 2500. Your manual probably tells you at best WD is optional for the weight of a 22. A trip to the scales would tell you what impact the the trailer has on your axles for sure, fender measurements would provide insight too.

Sway control is a different story from my perspective. Your mileage may vary - for me - it’s like not needing my seat belt for 99.9% of the miles I drive - but for that .01% it sure comes in handy.

Do what works for you.

[Profxd]

”Your Airstream has axles in the centre (slightly behind centre, but you get the point). It can pivot freely at the front connection. Thus it can sway. The resistance to sway at the coupler is not applied at the TV rear tires (which you claim have infinite friction). If you want to rely on the rear tires of the tow vehicle, look to a 5th wheel trailer, because that is where the pin is on that design, over the rear tires of the tow vehicle.”

JCL the resistance to sway does indeed come from the cornering forces generated at the tow vehicle rear tires as well as the trailer tires. The trailer rotates at its center of gravity when it sways so lateral forces are applied to the hitch pushing on the TV. This is why a shorter rear TV overhang is better than a long one.