I had 175,000 miles on my 04' Dakota that had the 4.7 in it when I sold it, and the only thing I ever replaced on it was the water pump ( besides the usual stuff, tires, brakes etc. ). Took about 45 minutes to do. It was a great truck with no issues. I personally would be looking at Hemi's anyway, your not going to get better mileage and certainly not anywhere in the ball park of the same power.