Need Yall's help .My old man has a 2001, 7.3 with about 89,000 miles, only problem was the trans at about 55,000 and upgraded it to the old/new design and has a supership in it. Here is the thing when the fuel gauge get's down to the first line, it starts a knocking sound, sometimes it gets really bad, but as soon as you put more diesel in it it goes away:dunno:. He just had the screen in the tank replaced,thought it would fix the problem because the plastic screen fixture was broken where it connects to the hose. Still doing it. It was knocking today, went to put diesel ,as I was pumping noise went away and wont come back till it get down to the first line.