I just had my 03 silverado duramax in the shop with an unknown substance in the fuel. Ran fuel level down week before down to min levels, then when fresh fuel level reached 1/4, problems started. Fule has some sort of spongy substance with metal meterial in it as well. Insurance company heard about a fuel armiture that might go bad and cause this type of substance in tank. Any one elese have this kind of problem?

Filling up at the same station?
Might be worth going back with a clear glass jar and putting a sample in. Take a look at what the fuel looks like. Looks bad, go have a chat with manager and mention the word "lawyer" in the conversation.

Interested in hearing what you find out.

What happened? Truck die? Not start....? Plugged filter?

I already covered that base. Also spoke to other major users of fuel, local truckers and tow operators. All have had 0 problems with this fuel station. (Shell).

Also fogot to mention, truck died and would not start twice. Plugged filter stopped fuel flow. Also replaced sending unit and 2 other items along with drain and flush tank and all lines. Neither the dealer or the insurance co has seen anything like this substance.

Did you put any kind of an additive in it?

No. Live in S. florida.

Additives illegal in S. Florida or something? In that humid climate additives are probably more important than in the northern areas of the country.

Maybe be algae growing....?

Just a guess.

Do you have a locking fuel cap?

Maybe you have a friend that dosen't like you and is filling your tank up with crap at night.

It happened to another member.

Just a thought.

Can yoou see what the metal type substance looks like? There was some failure of the CP3 pump in the 2001's from soft metal but I haven't heard of one for a long time. If it's the pump you will need to remove the tank and flush before runinng the metal back through the new pump.