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gandttimes · 10-16-2016, 09:18 AM

There is one way to prove it to yourself. Weigh the trailer by itself.
Now hook it up with your weight distributing hitch, and drive over the scales and just weigh the trailer.

George

Mrjkq · 10-16-2016, 11:21 AM

I don't believe towing a 28' will be a problem with that Hemi. I towed a 25' with the ecodiesel across the US without a problem & the semi has more power than the baby diesel. However, like stated above payload is an issue with some RAMs & mine was one as my payload was just over 800lbs. You're going to have to travel light because you subtract hitch & people weight there is not much payload left.

charlesk · 10-16-2016, 11:37 AM

We purchased a new 30' International. Looking at the specs of the Airstream, we then purchased a new Silverado 1500 6.2 with max tow package. The Silverado could pull the Airstream all day but the towing experience was awful.

Found out that our Airstream was over 1200 pounds tongue weight when loaded. Even after moving items aroud, we were still bouncing down the highway.

We're now towing our airstream with a Silverado 2500 diesel. Wow, what a difference.

I'd recommend weighing the airstream and the tongue and figure out what viehecle will be best.

Chuck

RamRider · 10-16-2016, 11:46 AM

Your Hemi will not be an issue, even with the 3.21. we pull all over west Texas and are never short of power. I do think you are going to be over loaded with that much hitch weight though. My 2015 has a load rating of 1444 (yellow sticker on door) are you sure that you have load rate correct.

We met some folks a week ago that were pulling a new 30ft airstream with a new Ram 1500 Hemi and were very happy with that combo. My opinion is when you reach a tt of 28 feet you are probably in need of a 2500 for better handling and braking.

You can always upgrade your truck later to get it right. There are some great deal right now on new Rams in this area and used ones have excellent resale.

Milo1952 · 10-16-2016, 12:10 PM

Quote:

Originally Posted by gandttimes

If you have a tongue weight of 1200lbs before you hook to the truck, you still have it after. All you have done is distribute it evenly @600lb rear and 600lb front. It doesn't magically disappear.

George

I may be mistaken but i do believe that even though the tongue weight remains the same some of the weight is also distributed to the tt axels as well, distributing the the downwards force to to front and rear on TV and also
to the TT axels as well reducing the net tongue weight on the TV

Milo1952 · 10-16-2016, 12:13 PM

Quote:

Originally Posted by gandttimes

If you have a tongue weight of 1200lbs before you hook to the truck, you still have it after. All you have done is distribute it evenly @600lb rear and 600lb front. It doesn't magically disappear.

George

I may be mistaken but i do believe that even though the tongue weight remains the same some of the weight is also distributed to the tt axels as well, distributing the the downwards force to to front and rear on TV and also
to the TT axels as well reducing the net tongue weight on the tv

Elbo · 10-16-2016, 12:33 PM

Now I know why when I am on a two lane road and see a truck and trailer coming toward me I pull over and stop if possible.

Sodbust1 · 10-16-2016, 12:58 PM

We pull our 28 foot Overlander along with our 1100 lb Bahama Rhino in the bed just fine...right at the limits with our 1500 tradesman hemi...

Mgieselman · 10-16-2016, 01:21 PM

I have a 1500 Limited Ecodiesel with a payload rating of 1150, tows great on the flats but it's under powered and over payload pulling our 28'.

The truck has the air suspension and was recently in for service, one of the codes stored in the ecu was "over payload".

gandttimes · 10-16-2016, 02:32 PM

Quote:

Originally Posted by cliffcharb

Grandtimes please explain. I understand how WD systems work and have scale tickets to verify what I posted.

Hi cliffcharb. Wasn't ignoring you. It took me time to find the proper explanation that even I could understand.

How a weight distribution hitch works
This summary tries to explain WHY a weight distribution system might be necessary and WHAT a WD system does to improve a rig's handling:

Without a WD system, the tow vehicle's rear axle load could significantly increase due to leveraging of the tongue weight. Conversely the front axle load will be decreased. These axle load changes will make most tow vehicles "unlevel". The decreased load on the front axle can cause a loss of steering control and braking difficulties. The increased rear axle load might exceed that axle's rating, and the load on the receiver might exceed its rating.

A weight distribution system enables a tow vehicle to more effectively handle the tongue weight of a trailer by removing some of the load from the tow vehicle's rear axle and distributing it to the tow vehicle's front axle and the trailer's axle(s). Note - When the WD system is engaged the actual tongue weight does not change. Recommended tongue weight is from 10% to 15%.

Consult your owner’s manual to determine if your vehicle is suited for a WD system. Some are not due to frame construction and/or suspension.

Several recent posts have discussed WD hitches. In one older post a member stopped using his because he felt it was contributing to sway by decreasing the "tongue weight". I hope the following will give a better idea of what the WD hitch does and does not do. Questions and comments are welcome.

Example assumptions:
TV wheelbase = 130”
TV rear axle to ball coupler = 65”
Ball coupler to TT axles = 200”
WD spring bar length = 30”
WD spring bar rear end load = 1000 lbs/bar = 2000 lbs total

How the WD hitch works:

Spring bar tensioner pulls UP on rear end of bar and DOWN on TT tongue. DOWN force of 2000 lbs on TT tongue adds a load of 300 lbs at TT axles.
This is calculated using ball coupler as the fulcrum: 2000x30/200 = 300.

Now, having added a load of 300 lbs at the TT axles, we must balance the TV/TT teeter totter. Using the TV’s rear axle as the fulcrum, to balance the 300 lbs at the TT’s axles we must add some load at the TV’s front axle.
The lever arm from the rear axle to front axle is 130”. The lever arm from the rear axle to the TT axles is 65+200 = 265”.
The required balancing load at the front axle is 300x265/130 = 611.54 lbs.

Or, we can calculate the reaction at the TV’s rear axle by treating the TV/TT as a lever with the fulcrum at the TV’s front axle.
The lever arm for the 300 lbs at the TT’s axles is 130+65+200 = 395”.
The lever arm for the rear axle is the wheelbase = 130”.
Since the TT axles are “lifting up” with a force of 300 lbs, this translates to an “uplift” at the rear axle equal to 300*395/130 = 911.54 lbs.

Summary of axle load changes:
TV front axle 611.54 lbs ADDED
TV rear axle 911.54 lbs REMOVED
TT axles 300.00 lbs ADDED

Now it is interesting to consider what happens at the hitch.

DOWN force of 2000 lbs on TT tongue adds a load of 1700 lbs at ball coupler.
This is calculated using TT axles as the fulcrum: 2000x170/200 = 1700.

The UP force of 2000 lbs on the rear ends of the spring bars produces an UP force of 2000 lbs at the hitch end of the spring bars.

The UP force of 2000 lbs minus the DOWN force of 1700 lbs on the ball gives a net UP force of 300 lbs at the hitch.

The vertical load on the receiver has been reduced by 300 lbs.
The vertical load transmitted through the ball has been increased by 1700 lbs.

SUMMARY

It is interesting to note that TT weight and “tongue weight” do not enter into these calculations. The WD hitch does not distribute “tongue weight”. It simply removes load from the TV’s rear axle and distributes it to the TV’s front axle and the TT’s axles.

Now there; wasn't that easy!
PS: This is NOT my original work. Not even sure where it came from.
Attached Thumbnails

rostam · 10-16-2016, 02:42 PM

I believe forum member Ron Gratz came up with the calculation referenced in your post.

gandttimes · 10-16-2016, 03:26 PM

Quote:

Originally Posted by rostam

I believe forum member Ron Gratz came up with the calculation referenced in your post.

Thanks. I got it from an SOB forum.

rostam · 10-16-2016, 03:57 PM

Quote:

Originally Posted by gandttimes

Thanks. I got it from an SOB forum.

Right, I believe he is on the SOB forum as well.

Baruke · 10-16-2016, 04:18 PM

Those Airstreams are easy to pull and your Ram shouldn't have any trouble!

Williker · 10-16-2016, 04:31 PM

Any weight that is transferred forward of the rear axle of the Tow Vehicle and rear of the front axle of the Travel Trailer is no longer counted as Tounge Weight. Any weight thay is loaded into the tow vehicle Rear of the tow vehicle's rear axle is also counted as tounge weight.
This is why some vehicle manufacturers list different tounge weight limits for towing with a weight distribution hitch.
The rear axle on the Tow Vehicle and the front axle on the Travel Trailer being fulcrum points in the equation. Weight to the front and rear of these points would detract from the weight in between (tounge weight) but not overall weight.

Naper · 10-16-2016, 04:43 PM

Clear as Mud !!!

rostam · 10-16-2016, 05:03 PM

My understanding is that tongue weight never changes. The effect of tongue weight on axle weights does however change with application of a WDH.

gandttimes · 10-16-2016, 05:20 PM

The basic problem, though is that if you have a payload capacity of 1000Lbs and a tongue wt of 1200lbs ( rounding off) you are going to be overloaded.

George

Williker · 10-16-2016, 08:04 PM

Quote:

Originally Posted by rostam

My understanding is that tongue weight never changes. The effect of tongue weight on axle weights does however change with application of a WDH.

It moves the pivot point on your tow vehicle Forward effectively creating a longer lever and moves the center pivot point back 2 feet to where your spring bars are attached shortening the trailer lever. This makes the compound mechanism of your weight distribution hitch system carry less tounge weight. If you measure tounge weight directly under the ball, it will be less weight because of the class 2 lever of the weight distribution hitch.

Holy Grail · 10-16-2016, 08:43 PM

I did it. I towed a 28' Flying Cloud with the zEal 5.7 Hemi. In general it's doable, but I strongly don't recommend for the Rockies. I ended up selling the Ram 1500 and getting a Ram 2500. Cummins. The Ram 2500 Cumming can tow my FC 28 up the tallest mountain. Love the exhaust brake!!