Reese Dual Cam Set Up...

[Ron Gratz]

Originally Posted by Jim Flower

I think the guys that came up with "100% FALR" are all former art critics or theorists. Show me some objective test data that confirms superior handling and safety performance versus equal squat and I will happily become a disciple.

Jim, I think you and I are using two different definitions of "equal squat".

When I use the term, "equal squat", I am referring to adjusting the WDH to cause the front and rear of the TV to drop by an equal amount.
If the front and rear springs have equal spring coefficients, this would be about the same as adjusting the WDH to cause equal loads to be added to front and rear relative to the unhitched loads.
IOW, my definition of "equal squat" relates to equal added load.

Some time ago, you posted your WDH was adjusted to give equal GVW for the front and rear axles -- 3300# each, I believe.
The tongue weight was stated to be 1250#

It is quite unusual for an unhitched TV to have equal front and rear GVWs.
Usually, the unhitched front GVW is considerably larger than the rear GVW.
I'm guessing that your unhitched TV had about 3100# on the front and 2550# on the rear.
If those guesses are in the ball park, the TW plus WD would have caused about 200# added to the front axle and about 750# added to the rear.

A 1250# TW should have caused about 660# to be removed from the front axle.
The WDH would need to add 860# to get a net gain of 200#.
The calculated FALR would have been about 860/660 = 130%.
I estimate a FALR of 160% would have been required to achieve equal added loads for your front and rear axles.

Therefore, it appears your WDH was adjusted to put you half way between the art critics/theorists and "equal squat".

Ron

[Rhino33]

Originally Posted by TomW

I have the old style Reese hitch, and my goal with it's seven-link-total chain, was to set up for the spring bars to be roughly parallel to the A-Arm while deflecting a healthy amount. I have three (3) links under stress.

There is an Airstream Article, central to what I thought my goal was at my website (link in signature). I wrote the article because no one in the business had one for me to read.

It would be great to read an article, in print, from someone with say, 40 years in the bidness on the subject.

Tom

Tom - Thank you so much for the info on the older style Reese hitch. That is the hitch that we have and greatly appreciate your sharing! BTW - what a great trailer and website!!

[Jim Flower]

Ron, thank you very much for your thoughtful response. We are on the same page when we are speaking of equal squat. I simply try to ensure that my Delta at the wheel wells remains the same loaded versus unloaded. Usually the rear Delta is about half an inch lower when loaded versus unloaded. Of course now, with the 2014 Jeep Grand Cherokee with the air suspension, the vehicle sits perfectly all the time regardless of loading. So I did my initial set up with the air suspension off and I had to have the Hensely cranked up to full blast in addition to a shank modification to increase the downward angle of the weight distribution bars in order to achieve a decent weight distribution. That is about half an inch lower at the rear wheel well. The results as shown by the weigh scale ticket were 2992 front, 3630 rear, and 7634 on the Airstream. I don't have unloaded weights.
So I am not really where I want to be weight distribution wise, but the whole contraption seems to handle really nicely, so I am a happy camper. Jim


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[Gringo]

now I'm getting confused. Hensley? I thought this was specific to Reese dual cam?

And if my current setup causes the rear fender well to do all the "squat" and the front fender well to remain the same height, does it sound like I am close to dialed in? by the way, before installing the Reese, using a weight carrying drawbar, when I put the weight of the trailer on it, the rear of the truck went way down while the front went up slightly. So I don't think friction in the linkage is preventing it from moving upwards if the forces tell it to move upward.

[Jim Flower]

Gringo
Yes. Please forgive my wandering about. I used a Reese Dual Cam for many years and it is still my reserve hitch for when my Hensley brakes. The principle for transferring weight is still the same. They just do it in a different manner. Jim


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[Jim Flower]

Brakes? Try breaks. I'm using the mic and sometimes it has its own way of spelling. Jim


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[Ron Gratz]

Originally Posted by Jim Flower

---The results as shown by the weigh scale ticket were 2992 front, 3630 rear, and 7634 on the Airstream. I don't have unloaded weights.
So I am not really where I want to be weight distribution wise, but the whole contraption seems to handle really nicely, so I am a happy camper.

Jim, your scales numbers, combined with estimated dimensions for your TV/TT and estimated unhitched axle loads, indicate a FALR very close to 100%.

I'll report to the former art critics and theorists that the FALR of 100% causes you to be a happy camper.
Would I be going too far if I also reported you are ready to become a disciple?

Ron

[Jim Flower]

Originally Posted by Ron Gratz

Jim, your scales numbers, combined with estimated dimensions for your TV/TT and estimated unhitched axle loads, indicate a FALR very close to 100%.



I'll report to the former art critics and theorists that the FALR of 100% causes you to be a happy camper.

Would I be going too far if I also reported you are ready to become a disciple?



Ron

Isn't that a riot. Now I am going to have to weigh the Jeep empty just to confirm that I will have to find another reason for sometimes being antagonistic. Yes, too far at this time. It takes a while get used to the idea. I will come back here to report. Again, thanks Ron. Jim


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[Bajaexplorer]

Originally Posted by Ron Gratz

Jim, your scales numbers, combined with estimated dimensions for your TV/TT and estimated unhitched axle loads, indicate a FALR very close to 100%.

I'll report to the former art critics and theorists that the FALR of 100% causes you to be a happy camper.
Would I be going too far if I also reported you are ready to become a disciple?

Ron

quite concerned about your statements when you are only guessing and do not have the complete data of the empty vehicle weight. Also with these self proclaimed jesus type of opinions " this is the right path to perfection" or you are an infidele if you do not follow me. My concern is this obsesive compulsion that you have to desqualify other members on this forum that have a different opinion and approach and that have compilated real data on the field for a number of years and are still working on the field.what is the point then? l will suggest you write the book, the manual, and most than anything your field test and experience, what have you learned from your own experience, specially considering the tv and its capabilities, not all trucks will break or have a catastrofic failure if you overloaded them with extra 60pounds correct? good luck.

[Jim Flower]

Hi Ron,
I got another set of weights this week end. Jeep unloaded front axel 3080, rear 2960, and for some unknown reason trailer axel but there was no trailer attached, 20 lbs, for a gross weight of 6060 lbs.
Jeep loaded front axel 3000, rear 3700, Airstream 7600 lbs.
So it would appear that I am not getting as much weight forward as I thought, based on my measuring wheel well heights and what has me really puzzled is that both the front and rear well well measurements were less loaded vs unloaded with the air suspension turned off. I really appreciate your comments and it would appear that I may be well on my way to becoming a FALR believer, even on a short wheel base vehicle. Jim


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[Bajaexplorer]

Originally Posted by Jim Flower

Isn't that a riot. Now I am going to have to weigh the Jeep empty just to confirm that I will have to find another reason for sometimes being antagonistic. Yes, too far at this time. It takes a while get used to the idea. I will come back here to report. Again, thanks Ron. Jim


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Ron, from my previous reply, I did no mention that you started a tread called underhitched what exactly is your point, and since the underhitched is all about the " soft performance of the TT " so what goes, this is the forum to talk about it.... thank you man.

[Ron Gratz]

Originally Posted by Jim Flower

Hi Ron,
I got another set of weights this week end. Jeep unloaded front axel 3080, rear 2960, and for some unknown reason trailer axel but there was no trailer attached, 20 lbs, for a gross weight of 6060 lbs.
Jeep loaded front axel 3000, rear 3700, Airstream 7600 lbs.---

Jim, thanks for posting the new weights.
The 20# reading for the "unloaded" trailer axle pad represents the resolution of the scales. It's not uncommon for a weight to be off by plus/minus 20#.

The scales numbers indicate a tongue weight of 763# with 103# transferred to the TT's axles.
The indicated trailer weight is (3000+3700+7600)-(3080-2960) = 8260#.

The indicated TW of 763# is unexpectedly low for your trailer.
Also, the unloaded weight of 6040# is about 800# higher than the published curb weight for your TV.
Does it seem reasonable to you that you would have had 800# of occupants and cargo in the GC when it was weighed?
Was the load of occupants and cargo in the GC the same for both the unhitched weighing and the hitched-with-WD-applied weighing?

---So it would appear that I am not getting as much weight forward as I thought, based on my measuring wheel well heights and what has me really puzzled is that both the front and rear well well measurements were less loaded vs unloaded with the air suspension turned off.---

If you hook up the WD bars by first raising the tongue with the tongue jack --
the upward force on the ball will cause load to be removed from the rear axle and added to the front axle -- just the opposite of what happens when TW is applied to the ball.
An upward force of 1000# could cause about 500# to be added to the front suspension. The added load would depress the front suspension.
When the tongue jack is retracted, the load on the front suspension will decrease -- but, hysteresis effects in the front suspension components could result in the front-end returning to a lower height than one would expect.
This could explain why the front-end height when hitched with WD applied was less than when unhitched -- even though the hitched load was less than the unhitched load.

I really appreciate your comments and it would appear that I may be well on my way to becoming a FALR believer, even on a short wheel base vehicle.

Your new scales data indicate a FALR value of 78%.
This falls in the range of FALR specifications from Ford, GMC/Chevrolet, Toyota, Equal-i-zer, and Reese which vary from 50% to 100%.

However, we still need to consider the seemingly low tongue weight and high unhitched TV weight indicated by your scales data.

Ron

[Jim Flower]

Originally Posted by Ron Gratz

Jim, thanks for posting the new weights.

The 20# reading for the "unloaded" trailer axle pad represents the resolution of the scales. It's not uncommon for a weight to be off by plus/minus 20#.



The scales numbers indicate a tongue weight of 763# with 103# transferred to the TT's axles.

The indicated trailer weight is (3000+3700+7600)-(3080-2960) = 8260#.



The indicated TW of 763# is unexpectedly low for your trailer.

Also, the unloaded weight of 6040# is about 800# higher than the published curb weight for your TV.

Does it seem reasonable to you that you would have had 800# of occupants and cargo in the GC when it was weighed?


No. I had a max of about 450 of passengers and cargo.

Was the load of occupants and cargo in the GC the same for both the unhitched weighing and the hitched-with-WD-applied weighing?


No. About 50 lbs more on the unhitched weighing.

If you hook up the WD bars by first raising the tongue with the tongue jack --

the upward force on the ball will cause load to be removed from the rear axle and added to the front axle -- just the opposite of what happens when TW is applied to the ball.

An upward force of 1000# could cause about 500# to be added to the front suspension. The added load would depress the front suspension.

When the tongue jack is retracted, the load on the front suspension will decrease -- but, hysteresis effects in the front suspension components could result in the front-end returning to a lower height than one would expect.

This could explain why the front-end height when hitched with WD applied was less than when unhitched -- even though the hitched load was less than the unhitched load.



Your new scales data indicate a FALR value of 78%.

This falls in the range of FALR specifications from Ford, GMC/Chevrolet, Toyota, Equal-i-zer, and Reese which vary from 50% to 100%.



However, we still need to consider the seemingly low tongue weight and high unhitched TV weight indicated by your scales data.



Yes. I did have full water and full propane. I also have 4 AGMs in the front area. No spare. I thought I had about 1200 pounds of TW. I think I should take all my junk out of the Jeep and try weighing it again. Jim

Ron

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[Ron Gratz]

Originally Posted by Jim Flower

I think I should take all my junk out of the Jeep and try weighing it again.

Jim, if you make another weighing --
you can gain more information about load transfer if you take three sets of data:

1. TV front axle load on pad #1 and TV rear axle load on pad #2 for TV only. (WDH and bars should be in the receiver or in the rear of the TV).

2. TV front axle load on pad #1, TV rear axle load on pad #2, and TT axles' load on pad #3 for TT attached with no load on WD bars.

3. TV front axle load on pad #1, TV rear axle load on pad #2, and TT axles' load on pad #3 for TT attached with WD bars tensioned.

The occupants and cargo in the TV should remain the same for all weighings.
The air suspension should be "on" during the second weighing to keep the TT close to level.
The air suspension should be "on" when the WDH is adjusted. If not, the load transfer will be decreased when the air suspension does get activated.

Ron

[Jim Flower]

Ron
Thanks for the description. I am away on business this week but will get the weighing done next weekend when I get home if I recover from being jammed into a cigar tube for 4 hours. It's getting harder. I would much rather spend 4 days driving with my own bed to sleep in and my own stuff around me, which is what I do when I have more time. Jim


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[Ron Gratz]

Originally Posted by Flyingsilver

Ron, from my previous reply, I did no mention that you started a tread called underhitched what exactly is your point, and since the underhitched is all about the " soft performance of the TT " so what goes, this is the forum to talk about it.... thank you man.

Flyingsilver, I didn't notice that this post was directed to me. When I saw that you had quoted Jim Flower, I thought your comments were directed to him.

Yes, I did start a thread called "Underhitched" - Any Evidence of Damage to WD Bars? -- I had forgotten about it.

In Another thread on a different Forum, I suggested that WD bars could be sized on the basis of how much load one wanted to transfer rather than on the TT's tongue weight.
One member questioned whether this might result in overstressing of and damage to the WD bars.

Since I knew that some Airstream owners were using WD bars rated for considerably less than the TW, I posted here to see if anyone had experienced damage.
I didn't expect that there would be any damage, and none has been reported.

Sorry for the late reply.

Ron

[drboyd]

......

[BoldAdventure]

Reviving this thread to get some opinions. I am using 1000 lb bars. ( I might need to double check that)

Seems I am almost at 100% FALR

Cat tickets

First, just the truck loaded with all of us and some gear.
Steer: 4620 .lbs
Drive: 3740 .lbs
Gross: 8360 .lbs

The second pass is truck and Airstream but no weight distribution.
Steer: 4180 .lbs
Drive: 5140 .lbs
Trailer: 6780 .lbs
Gross: 16100 .lbs

So tongue weight is 960 lbs. Not bad.

Third pass, truck + Airstream with weight distribution applied
Steer: 4580 lbs.
Drive: 4620 lbs.
Trailer: 6900 lbs.
Gross: 16100 lbs.



To me it doesn't look like I have any real bend in my hitch.





I'm wondering if I should consider using a smaller bar, like 800lbs so that the ride isn't as harsh using a 3/4 ton.

Or should I just keep it like it is. Thoughts?

[dznf0g]

I used 800s with my 30' classic. Worked well.

[TomW]

I would DEFINITELY not use 1000 lb bars with your HD truck.

It would be nice if you could borrow a set of 550 lb bars - That's what I use for 460 lb tongue weight hitched to my HD truck and they could easily bend more than they do.

I will bet that your 960 lb tongue weight would put the perfect bend in them.

Tom