Need help

Been a lurker for a while decided its time to join.. Hope I am posting this in the right spot. I have a 2000 379 exhd with 60 series in it. Inframed 24,000 miles ago with a new head. Fuel started to turn black they replaced injector o rings 3 times and the crush rings too. When replaced o rings it seems to clear up the problem for about 2 weeks. It was still doing it so they replaced head and all o rings and crush rings again. Cleared up for about a week. Changed fuel filters yesterday and the fuel is black again. Truck has started to smoke black more than usual for about the last 4 days. I am at my wits end..all the fuel lines have been replaced. Fuel pump has been replaced . Inside of the tanks are black on the walls. Has anybody else had this problem? Truck will stumble every once in a while and blow white/blue smoke. It will only do it ever so often Just when you have throttle barley pressed and then Get down on it..computer has also been replaced along with all inter cooler boots CAC has been checked no leaks hose from compressor to intake has been replaced. Hopefully somebody can point me in the right direction..injectors have been changed also cleared up for about a week.

 

Have used biocide it did not change anything. After they change the parts any parts it seems to clear up but just for a bit then back to same thing. If it was the asphaltenes would it do it all the time? I have never had that problem.

 

Fuel filters are black..get fuel at a pretty busy place..got 2 guys that I run with we get fuel at same spot and they aren't having any problems. It's not a sludgy black.i have cut 2 sets of fuel filters open and have found no "sludge".

 

No slimy stuff whatsoever.. I can reach in the tank and rub the side and it's not slimy either..I'm thinking it has to be carbon or soot...and I may be wrong but I just don't understand how when they " fix" it it's good for a week or two then right back to the same thing... It will clog fuel filters in about 3 days. There has to be something else wrong???? Thank god for warranty but it's killing me on downtime.