Weight dist hitch subtracted from TV GVWR or GCVR?

Here is how I see it...

A Fiver's hitch is bolted to the bed, so part of the TV's weight. Think of unhitching
and what is left on the truck and what goes with the trailer

On a tongued...many different architectures for a one size fits all answer/opinion

Most will have the hitch as part of the TV...unhook and what stays with the TV
is on the TV's weight. What goes with the trailer will be part of it's tongue weight

A HA/Pro has the hitch as part of the shank and goes with the trailer to become
part of the trailer tongue weight...but since not traditional 'ball'
to speak of...can't really say what hitch weight goes where...

Receiver and Weight Distribution Hitch (head/ball/bars) become part of tow vehicle weight

Trailer tongue with anti sway control become part of tongue weight.

Ron Gratz wrote:
The good news is that, with a properly sized and properly adjusted WDH, a load equal to approximately 25% of the tongue weight is transferred from the TV to the TT's axles.
Therefore, with a conventional hitch and a TW of 1000#, you would add about 100# to the weight of the TV (due to the weight of the WDH),
and assume the TT adds an additional load of about 750#.

Well that is good news!!

Here's my situation. Since we're so "fluffy" we really have to watch tongue weight and consequently trailer weight, but we want to be able to sleep up to seven adults (some day), and the wife refuses to do any fabric-sided trailers, so hybrids and pop-ups are out. We also want about 1300lbs of cargo capacity. And the TV is a 2003 Ford Expedition. Thus I calculate that we're limited to 4,300lb seven adult trailer. There are very few sub-4,300 trailers with hard sides that sleep seven adults. (They are out there, but our choices are limited.) However, if I can subtract 25% of tongue weight, I can go up to a 5,106lb trailer. The market is much wider in that weight range.

Also, this means I can go from a 9% tongue weight to a slightly more comfortable 10% TW. I was uncomfortable not having much margin.

Can someone check my math?

Regular hitch



Hensley

Oops I didn't subtract 100lbs from the trailer weight so 5,006lbs. That's still much better than 4,300lbs.

I think you are underestimating the tongue weight. If those numbers are manufacturers advertised UVW numbers, they are notoriously wrong, and not wrong in your favor.

Another number notoriously wrong, is advertised curb weight. Anything added to the vehicle (dealer installed options / aftermarket accessories, undercoating, dirt, rust, etc) since it left the factory, added pounds to the curb weight and reduced available payload. Even something as simple as floor mats took about 15 lbs.

What you're trying to calculate, is so close to the edge, the slightest miscalculation, extra case of refreshments, unplanned passenger, or extra piece of firewood, will put you over. I think the underestimated tongue and curb weights are already going to do that.

I think you're putting too much faith in the WD hitch being properly set up and transferring the right amount of weight. Only way to be sure, would be to go to a scale, every trip.

You're putting yourself in a situation where you will need a scale at the door, to weigh every thing and everybody, going into both the tow vehicle and the trailer. You'll also need a tongue weight scale for loading the trailer to a specific tongue weight, everytime.

If the Expy has passenger "P" rated tires, you'll need to pump them up to max pressure, for towing. They were designed for comfort, not heavy loads.

Another area you may save a few pounds, is the WD hitch. Andersen makes a WD hitch with built in sway control, that only weighs 60 lbs, including brackets that are mounted to trailer tongue. On heavier trailers, it's a little weak on weight transfer, but, it works well with lighter units, and it weighs almost half that of many other hitches. An added benefit is, it's quieter than most hitches, and because it uses no dirt attracting lube of any kind, it is cleaner.
Do a search (Andersen hitch) here on the forum. It has been discussed many times.

handye9 wrote:
I think you are underestimating the tongue weight. If those numbers are manufacturers advertised UVW numbers, they are notoriously wrong, and not wrong in your favor.

I don't have a trailer yet, so there are no manufacturer's advertised UVW numbers in my spreadsheet. I need to see what I can safely tow and then I go shopping.

Also there is a 20% buffer in the trailer cargo. So really 1,040lb trailer cargo on the spreadsheet.

handye9 wrote:
Another number notoriously wrong, is advertised curb weight. Anything added to the vehicle (dealer installed options / aftermarket accessories, undercoating, dirt, rust, etc) since it left the factory, added pounds to the curb weight and reduced available payload. Even something as simple as floor mats took about 15 lbs.

Understood. A necessary step will be to get on a scale with our expected touring load.

The weak link is GVWR and according to these calculations it's 27lb under. I put in a 3% buffer as well, and I estimated our body weights very conservatively. (Shoot maybe I'll lose weight.) For trips like I'm intending I'll just have to be religious about what does and does not go in the cabin. There go the floor mats :D

handye9 wrote:
I think you're putting too much faith in the WD hitch being properly set up and transferring the right amount of weight. Only way to be sure, would be to go to a scale, every trip.

You're putting yourself in a situation where you will need a scale at the door, to weigh every thing and everybody, going into both the tow vehicle and the trailer. You'll also need a tongue weight scale for loading the trailer to a specific tongue weight, everytime.

If that's what I have to do, then that's what I have to do.

handye9 wrote:
If the Expy has passenger "P" rated tires, you'll need to pump them up to max pressure, for towing. They were designed for comfort, not heavy loads.

They are 265/70R17, 115 load index (2,679 lb), T speed range (118mph) SL (Standard Load). So I'd say they are adequate, wouldn't you?

handye9 wrote:
Another area you may save a few pounds, is the WD hitch. Andersen makes a WD hitch with built in sway control, that only weighs 60 lbs...

Ok great! Will look.

What do you consider a safe buffer for the GVWR? 20%?

cdevidal wrote:
What do you consider a safe buffer for the GVWR? 20%?

According to this thread, there should be no concerns being right at GVWR. It gets more controversial when going over, but if I have to get fanatical about weights so I don't go over, I will.
Is being a little over GVWR no worse than doing 60 in a 55?