I once measured my truck to see what happens when I hook up the TM. My rear bumper sags about 3/4 inch and the front bumper lifts about 1/2 inch. I do not use a WD hitch, but I have a rather large truck. I would think that with a WD hitch you would be able to keep both front and rear sag to be identical. You could probably even push the front down, but that is likely not a very good idea.
It seems to me that it would be desirable to have the same sag both front and rear. That way you won't have a problem with headlight adjustment.
