I've only done my research on the 4.0, but I have a really good 2.5 available to me now too, with A LOT more extras than the 4.0. But I do highway driving frequently. I know these aren't considered the greatest daily drivers, but I really don't care, I like 'em. I've heard some bad things power-wise about the 4banger, what're your thoughts on it? In either truck I plan on cruising at no more than 65-70mph... this is really frustrating me... and I'd really rather not drop a 6 cyl into it. Any thoughts are appreciated.