CAT scale weights

[amabee]

Ok, so I took our X17Z and TV to see where we are at. I have a fair idea how this all works but could use some help/advice.

The trailer was fully loaded to go camping and was over by 40lbs, that I can fix by moving a few things to the truck.

The main concern I have is, if I am doing this right, the tongue weight with the bars engaged is 400lbs. With the bars hanging it was 620lbs. To me this seems like to much of a difference.

Here are my numbers, I don't know why the Gross weight with the trailer is off by 20lbs between the 2nd and 3rd weigh.

1st weigh:
Steer axle 3500
Drive Axle 2640
GW 6140

2nd weigh:
Steer axle 3600 spring bars engaged
Drive axle 2940
Trailer axle 3140
GW 9680

3rd weigh:
Steer axle 3280
Drive Axle 3480
Trailer axle 2940
GW 9700

My thoughts are to adjust this with the chains on the bars, if I add a link would that decrease the difference in tongue weights?
I thought had this all figured out, but all these numbers are making my head hurt

[Rustic Eagle]

Great job on your TV/TT CAT scale visit!!

Your loaded tongue weight remains the same, doesn't’t matter if the spring bars are engaged or not. What the WDH does is distribute the weight (to TV front axle & TT axle) that is located over the TV’s rear axle do to the “effect” of the TT’s loaded tongue being placed on the TV’s hitch ball, thus the weight placed on the hitch ball remains constant.

Based on your CAT scale results your loaded tongue weight is: 3rd weigh TV axles (3,280lbs + 3,480lbs) – 1st weigh GW 6,120lbs = 620lbs

Your loaded TT weight is: 2nd weigh GW of 9,680lbs - 1st weigh TV GW of 6,140lbs = 3,540lbs.

Recommended loaded tongue weight should be 10% to 15% of loaded TT weight. So at 3,540lbs = 354lbs to 531lbs tongue weight range, which suggests that you may want to relocate some cargo within the TT.

As far as the 20lb difference between the GW’s of the 2nd and 3rd weighs, that is most likely the CAT scale tolerance error…., can be plus/minus 40lbs).

Ideally you want the WDH with spring bars engaged to return the same weight that was removed from the TV’s axle when the TT’s tongue was initially placed on the hitch ball. Your TV only weigh steer axle weight was 3,500lbs…, with your TV/TT hitched w/bars engaged the TV’s steer axle was 3,600lbs…, this means that you have returned an excess of 100lbs to your TV’s steer axle.

To avoid confusion, think in terms of “chain links-under-tension” at the snap-up bracket. IMO you may want to adjust your WDH so that you are a little closer to the 3,500lbs, thus you may want to “add” 1 more chain link under tension resulting in reducing some of the weight transfer. So if you are at 5 chain links under tension, try 6 chain links under tension. Don't worry about the rear axle weights or degree of squat.

GM front suspensions have suspension stops and if you transfer to much weight to the front suspension it will produce a stiff and rough ride.

With your CAT data you can also check your TV's axle limits, GVWR, and GCWR. also check the TT's GVWR.

You may have referenced the following JOF CAT scale info, but may be helpful to others as well: http://www.jaycoowners.com/showthrea...igh-Your-tt-tv

Hope this helps a little...., a lot of numbers to digest so feel free to ask if I can clarify anything.

Bob

[OnTheGo]

I'm trying to follow along here and maybe learn something. amabee states "The main concern I have is, if I am doing this right, the tongue weight with the bars engaged is 400lbs. With the bars hanging it was 620lbs." How does the tongue weight stay the same? Is the tongue weight 620 and the WDH gives it the effect of 400? I'm about ready to go through the weighing process myself.

His weight was distributed about 40% to the TT and 60 % to the TV front axle. Any signifgance there?

[Rustic Eagle]

OnTheGo,

Once the loaded TT tongue is placed on the hitch ball and the coupler is locked, the front of the TV rises and the rear of the TV squats do to the weight placed on the hitch ball. When the WDH is engaged the spring bars create a for/aft force within the ball mount sockets that is transferred through the TV's receiver and the TT's A-frame (a little physics in play here). The tongue weight placed on the hitch ball mounted on top of the ball mount remains the same.

The WDH while the spring bars are being engaged will raise the rear of the TV and lower the front of the TV and in effect be distributing weight that was located over the TV's rear axle..., not the tongue weight on the hitch ball.

The only way to determine accurately the actual loaded tongue weight on the TV (hitch ball) is with the spring bars dis-engaged.

The next time you hitch up your TV/TT, watch what happens at the WDH ball mount while the spring bars are engaged.

Originally Posted by OnTheGo

His weight was distributed about 40% to the TT and 60 % to the TV front axle. Any signifgance there?

Not really, the objective of the WDH in this case was to return 220lbs (3,500lbs - 3,280lbs) back to the TV's steering axle. The percentages will very from one TV/TT combination to another.

I can tell you that it took me a little while to get my noodle around how a WDH worked, but in time I found it to be a pretty slick device!

Bob

[amabee]

Bob, Thank you for the information, it has helped quite a bit.

Based on your CAT scale results your loaded tongue weight is: 3rd weigh TV axles (3,280lbs + 3,480lbs) – 1st weigh GW 6,120lbs = 620lbs

Your loaded TT weight is: 2nd weigh GW of 9,680lbs - 1st weigh TV GW of 6,140lbs = 3,540lbs.

Recommended loaded tongue weight should be 10% to 15% of loaded TT weight. So at 3,540lbs = 354lbs to 531lbs tongue weight range, which suggests that you may want to relocate some cargo within the TT.

I would agree, I was a little surprised it was that much, but I can move roughly 100lbs to the rear of the trailer. With that said would having a tongue weight slightly over 15% cause problems??

Ideally you want the WDH with spring bars engaged to return the same weight that was removed from the TV’s axle when the TT’s tongue was initially placed on the hitch ball. Your TV only weigh steer axle weight was 3,500lbs…, with your TV/TT hitched w/bars engaged the TV’s steer axle was 3,600lbs…, this means that you have returned an excess of 100lbs to your TV’s steer axle.

To avoid confusion, think in terms of “chain links-under-tension” at the snap-up bracket. IMO you may want to adjust your WDH so that you are a little closer to the 3,500lbs, thus you may want to “add” 1 more chain link under tension resulting in reducing some of the weight transfer. So if you are at 5 chain links under tension, try 6 chain links under tension. Don't worry about the rear axle weights or degree of squat.

Right now we have 5 links under tension, this was how the dealer set it up, I will try 6 links next time. I also noticed the steer axle increased in weight, it was about here I started to get confused, but it is making more sense now.

With your CAT data you can also check your TV's axle limits, GVWR, and GCWR. also check the TT's GVWR.

For the most part we are ok, except the TT's GVWR is 3500lbs, so I will need to relocate a few things to the truck. The pickup has a 7000lb GVWR and the front and rear axles are rated at 3950lbs each, so we should be good there.

Not really, the objective of the WDH in this case was to return 220lbs (3,500lbs - 3,280lbs) back to the TV's steering axle. The percentages will very from one TV/TT combination to another.

This statement helped maybe more than anything else, I did a fair amount of research on WDH but I don't recall anyone putting it quite that way, that actually makes sense in my little brain

Allen

[Rustic Eagle]

Originally Posted by amabee

snip....... I was a little surprised it was that much, but I can move roughly 100lbs to the rear of the trailer. With that said would having a tongue weight slightly over 15% cause problems??....snip

Allen,

Well, I lean more on the cautious side when dealing with the "lite" HTT's because the A-frames tend to be of a lighter grade material. As one increases the loaded tongue weight above 15%, keep in mind that additional WDH spring bar force is required (against the A-frame as well) to compensate for the effect of this weight on the TV's axles.

Your X17Z has a GVWR of 3,500lbs..., at 15% this is 525lbs. My definition of slightly over with the X17Z would be 25lbs, but anything more I would be looking at shifting some cargo around..... that's just me.

Yes, most folks are surprised at the actual loaded weights after visiting a CAT scale.

Bob

[amabee]

Your X17Z has a GVWR of 3,500lbs..., at 15% this is 525lbs. My definition of slightly over with the X17Z would be 25lbs, but anything more I would be looking at shifting some cargo around..... that's just me.

That is kind of what I was thinking, I am fairly certain I can get it down to 525, but that may be about it. The label on the tongue says not to exceed 975lbs, but the coupler is only rated at 700lbs, so yeah 620lbs. is starting to push it.

[Rustic Eagle]

I agree with your line of thinking

[OnTheGo]

Adjusting cargo and WDH so TV and TT are within manufacturer’s published weight ranges is not as easy as it first appears. And IMO necessary for personal safety and extended life of the equipment.

I have the same TT as amabee, the 2011 X17Z. Jayco published the hitch weight, leaving the factory as 415 pounds. On mine, the dealer added a 46 pound battery which sits immediately behind the tongue jack. The L brackets and associated hardware for the Fastway e2 WDH add another 12 pounds up front. That’s a total of 473 pounds, or 13½ % of the 3500 allowable gross standing on the dealer’s lot. That leaves 1½ % or 52½ pounds you can add to the tongue weight – not much – but doable with a little planning.

Another loading / weight issue to consider is most of the storage space, the cabinets and under the sofa, are located in front of the axle. amabee’s TT, with the spring bars engaged, had an axle weight of 3140, leaving 160 that could be put on the axle. If I’m seeing this correctly, it might be slightly more than 160 because after the tongue weight is reduced there will be less transferred back.

We really like our 17Z and I’m willing to make those loading adjustments necessary to achieve proper weight and tow ratings. So, ANYTHING that isn’t necessary is gone. All the heavy stuff that’s left goes toward the axle – not on it. Tissues, crackers, pen and pencils, etc., are going forward. DMIL has to stay home. (Oops!)

My TV is a F-150 with a standard bed, and capped. Without a full size pickup as a TV, to “share the load” it would be tough.

Thanks amabee and Rustic Eagle for your time and effort to share this information.

[amabee]

It's definitely a little work with this particular trailer, but doable. I do agree, having some extra room in the TV is a major plus.
My plan is to move the spare tire off the tongue into the bed of the pickup, it weighs roughly 45lbs which will bring the GTW down to 3500lbs and reduce my current 620lb TW. During our test run all of our duffel bags with clothes etc were at the front of the trailer, about 50lbs, these will now be placed right inside the door to get them off the tongue. This should get my TW down around 525lbs.

If I am understanding this all correctly, my axle weight on the trailer should go down some. Aside from the removal of the spare tire, which will have some affect, my spring bars are currently set "to tight" for lack of a better way to say it, meaning they are transferring to much weight to the front of the TV and to the trailers axle. By putting another link under pressure, the tongue will go down some, placing more load on the hitch and the rear axle of the TV.

Basically all I need to do is move the spare tire, which is not a big deal, I don't like where it is anyway, and move our clothes back in the trailer. So in our case anyway, no real compromises. There would, however, be no way to know all of this without going to a CAT scale and actually weighing it.

Allen

[OnTheGo]

Basically all I need to do is move the spare tire, which is not a big deal, I don't like where it is anyway, and move our clothes back in the trailer. So in our case anyway, no real compromises.

Those are realistic adjustments and weights. You are going to be well within ratings without much more than that.