There are THREE hitch ratings. 1. Tow rating 2. Tongue weight rating without WD 3. Tongue weight rating with WD
I suspect you are confusing the ratings on your hitch with and without the WD. The newer PUs have increased their tongue weight rating without WD to 600 pounds
No argument from me. If GM and Ford no longer advocate using WD or using it to a lesser degree than prior, then the reciever rating has to be higher to accommodate the tongue weights. I suspect they are since the Ford one ton comes with a 2.5 inch receiver stock and can tow trailers into the mid teens. Ford must know that even with only 10 percent on the tongue a mid teen trailer will have somewhere around 1300-1500 pounds on the receiver.