As it was explained to me:

WC vs. WD does not have anything to do with the strain on the drivetrain. Hence towing capacity is towing capacity, with either setup.

The hitch receiver itself is where the WC/WD comes into play.

Correct, but it does make the heavier loads at the upper end of the rating more pleasant and manageable by spreading the tongue weight over both axles of the tow vehicle instead of just loading the rear axle. I can very much feel the difference when the trunion bars are on.

Any pics of WD systems on your big boat trailers???

Only have a couple distant shots of the Eagle/382 trailer back in Ohio from file photos. The trunion bars are not attached in the first photo, but it does show the WD head. The second photo shows the trunion bars attached, but not the head. These are 1000# bars. Brackets clamp on the channel on the tongue of the trailer. I can shoot a few of the 260 SS/Prestige trailer thats out here in Vegas when I get a little time. Working my backside off until next Thursday ...

Some info from Reese website very similar to what I use:

http://www.reese-hitches.com/product...nion_Bars,7903

One needs a Pole Tongue Adapter for putting a WD system on a boat trailer:


http://www.etrailer.com/Accessories-...se/RP3280.html
(The one I had.)

http://www.etrailer.com/Accessories-...e/RP58393.html
(Was not on market when I was shopping.)

More info here:
http://www.fourwheeler.com/techartic...g/viewall.html

Not according to the Ford towing guide. The max towing number they provide is when using a WD hitch, otherwise it is a max tow rating of 8500. The GCVFR is from typing on a cracked iPad screen. :)

What years did the tow behind capacity exceed 12,500?
My 96 diesel F350 crew cab is listed at 12,500 bumper/receiver hitch and 17,500 5th wheel/goose neck.