Don't know about the loss of power, but the fuel sender in these trucks is a problem. My gauge has been on E for the last 5 years. I fill it up, it says F, but by the time I drive 100 miles, it drops to about 1/2, then 10 miles later it's on E. And it's even worse when I'm towing. I've just been using the odometer, and don't worry about it. I'll fix it one of these days. These trucks have to have a quirk, somewhere. I figure if I don't fix the fuel gauge, then something else won't break.
Jim