fuel lines went bad

[pimajim]

My 2001 Duramax/2500HD started dropping into the limp mode, got worse and worse, local dealer wants to replace injectors, Did not seem to be the symptom. Finally I noticed the frame under the fuel tank was dripping fuel.
Garage in Tucson found the fuel lines (both) were FULL of leaks!! Also lines to the fuel filter were rotten. Any idea what would cause this, always get my fuel at local shell station or truck stops if traveling.
PS it took 3 weeks to get fuel lines out of GM, cash only.

[trbankii]

Last time I was under my '93, I was surprised at how rusty the fuel lines were and just a little surprised that they AREN'T leaking considering how bad they look. Up here, I attribute it to salt on the roads in the winter but I have to admit that the underside of my truck looks worse than any of my other vehicles.

You say the lines are leaking, but how do the lines look? Corroded? Or is the corrosion coming through from the inside?

[DmaxMaverick]

I've noticed the fuel lines under the hood "checking" (like old tire sidewalls), but not leaking. I have, on only a couple occasions, notice a fuel drip below the fuel tank (when I "top off" the tank), and it's "wet" around the strap. Doesn't seem to be regular or a lot, and I'm not looking forward to dropping the tank (or lifting the bed), but will likely be doing it soon.