I forgot to add this;

Will the single rear wheel provide this?  I have read that with the Gross
trailer Wt. above 10,000 lbs. one should go to Dual rear wheel or the larger
trucks and beyond?  If someone can point to an easy source to understand
where these calculations are described I would really appreciate seeing that
link or links.

Thanks,
Jon

That pin wt is only 14%.   It looks like you might be using the dry pin wt
listed in the brochure, but this applies to the dry wt of the trailer.  You
take these two dry wts and get the pin wt percent and then apply that
percent to the 12K to get the pin wt that goes with the 12K.   Typically,
pin wt will be~19% (some Wildcats being an exception at ~15%)  19% of 12K is
2,280 lbs pin wt.

Say the Diesel 4X4 truck weighs 7,500 lbs and has GVWR of 10K, that leaves
2,500 for payload/cargo.  The hitch in the bed might weigh 250 lbs so that
and the pin wt of 2,280 is 2,530lbs.  Now add people , dogs, gasoline,
assorted stuff.  Say another 600lbs.   Now the truck is over its GVWR by
~600lbs.

The other number is the GCWR  Diesels can pull big amounts.  But truck
weighs a lot too.  Say GCWR is 23,000 and truck weighs (loaded for trip)
7,800lbs.  Trailer can weigh 15,200.   But pin wt will be (using 19%)
2.900. So now you need the 1-ton and probably a 1-ton dually.

Look at another truck, a Chev 2500HD gas 6.0/4.10 weighs 6,700 with hitch
and people, gas, dogs. GVWR is 9,200.  Can take 2,500 pin wt.  (more than
the Diesel 4x4.) but GCWR is only 16K so max trailer is 9,300lbs (not the
10,000 as stated in the driver's manual!!!) (Diesel and transmission add
700lbs, 4X4 add 300lbs) so same truck with those options would weigh 7,700
and have pin wt capacity of only 1,500.

So you want a truck with a big engine to pull a big trailer but with enough
carrying capacity to take the carrying weight.  Lose the 4X4 and save
300lbs!   Maybe go with the big gas 8 instead of the Diesel and save more
pounds. (pay lots for gas!)
SRW 1ton Diesel with no 4X4?  Got to be careful with the math.  SRW 1ton has
only slightly more carrying capacity than  the 2500HD.   Big jump in
carrying capacity and same pulling by going to DRW.

As seen above, the trailer towing capacity in the truck brochure is with the
truck not loaded for a trip and without the heavy option package either.
You have to get the real weight of the truck with all your stuff in it, a
full tank, and the hitch installed, and go weigh it before you know for sure
what is left over for pin wt.  You can get reasonable example weights from
others here or similar forums who have that truck.

Regards,
Barry

Hi,
The 5th wheel rating is high because with a 5th wheel you put a lot of
the towed weight into the box of the pickup truck as pin weight.
Usually 20 to 25 percent of the weight of the trailer.  So the max 5th
wheel tow rating is based on a weight that they figure won't overload
the vehicle and stay within it's tow rating and GCWR.  If you use a 20
percent pin weight with the 15400 lb max 5th wheel towing you get a pin
weight of close to 3100 lbs. 25 percent 3850 lbs.  If the cargo carrying
capacity is less then this with the truck fully loaded to travel, or if
this puts the truck over it's GVWR or GAWR or over it's GCWR you can't
tow that heavy of a vehicle, legally...  

With a 5th wheel the things to look at in a truck to pull it,  is it's
cargo carrying capacity it's GVWR and GAWR and it's GCWR capacity.  The
truck has to have a cargo carrying capacity that can safely carry the
pin weight of the 5th wheel plus the weight of the hitch, fuel,
passengers and anything else you may have in it.  And it fully loaded to
travel should stay under it's GVWR, GAWR and it's GCWR.

Typically 5th wheels have pin weights that are around 20 percent or so
of their total weight.  If you have a trailer that has a GVWR of 12,000
lbs.  then the pin weight should be somewhere in the 2400 lb to 2600 lb
range fully loaded.

With the truck you mention above the cargo max weight according to the
Ford site is 4000 lbs.  It's GVWR is 11,400 lbs. So you should have no
problems with a 12,000 lb. 5th wheel.  Unless you get a fully loaded
truck and carry rocks around with you.. :)

Take care and Happy Campin...