Thanks for the info so far. Think I'm going to try the 35" Terra Grapplers. Looked at the Trail Grapplers, but I don't do any off-roading (aside from some construction sites) and I like the clean sidewall of the Terra's.
We'll see how it all goes.

 

my 2002 f1504x4 5.4l was slow on stock gears and 35's. Got 4.56's in there now and the truck really woke up in the low end and its not reving too high on the interstate. I could barely get up to speed pulling my 22 ft grady white(heavy-*** boat) before now it pulls fine and the transmission isnt overworked.