I have about 135,000 miles on my 5.4L in my 2000 f150 and it still runs like it is new. The 5.4L is hands down better than the 4.6L. If you want a truck that throws you back in your seat when you step on the gas the 5.4L is the one you want. The 4.6L is a dog of a motor. If you interested in towing anything the 5.4L is still the better choice. As far as durability, you can kill any motor if you dont take care of it. If taken care of properly the 5.4L will last quite a while. | 
