Originally Posted by cpaharley2008
In the Ram models the bed is a 1 foot shorter with the crew vs the quad cab, thus the pivot point is 12" closer in the crew cab models.
You can get a Ram 1500 with a 6'4" box in either quad or crew cabs. The crew cab is also available with a 5'7" box as an alternative: the 9" difference in box length comes entirely out of the space between the cab and the rear axle, so if you place the hitch in the same place relative to the axle
in these two box lengths of Ram 1500 (regardless of cab) the pivot point is 9" closer to the cab with the shorter box.
If you compare any of the 6'4" box trucks - regular, quad, or crew cab - they'll have the same clearances for the trailer because all the extra length of the bigger cabs is in the cab area (so it adds to the wheelbase) - no change in the back. Quad adds 20" over regular; crew adds another 9" over quad.
The rear overhang (rear axle to tail end) length is the same (48.4") in both 5'7" and 6'4" Ram 1500 variants, so in that way it is just like the F-150: if you place the hitch in the same place relative to the axle
in any of these trucks you will have the same tailgate clearance. There is still a Ram 1500 with an 8' box (only with standard cab): that one has two inches more rear overhang (probably so it will fit on the same frame length as a crew cab with 5'7" box), so it would have 2" less tailgate clearance if you place the hitch in the same place relative to the axle
One of the advantages of typical pickup trucks over other vehicle styles is the range of choice in configuration; that is also a problem with these trucks.
In this case there are three cabs, three box lengths, and three wheelbases, with five available combinations... all of just the 1500 model. (The F-150 has three cabs, three box lengths, five wheelbases, and six available combinations, but all six have the same rear overhang).