2000 Chevy 3/4 ton stopped and won't start.

[bwood]

Like clinebarger said, the dealer can help narrow it down by the VIN. GM is bad about putting 2 to 3 different pumps in the same truck for different emissions or chassis types. The best bet would be to go ahead and lift the bed, some guys have had luck just getting it high enough to get to the pump on the driver's side and not actually removing the bed. Once you can see the top of the pump assembly, there should be a 3 letter code on top of the pump. This is what the parts stores refer to distinguish between the two different pumps. I beileve the codes will be GFT (which I think yours will be) or GDJ, GFK (these are listed as Calif. emissions), but only way to be sure is to look at the top of the pump. I would also recommend finding a Delphi/AC Delco pump. These are factory pieces that can be purchased at NAPA, Oreilly or the dealer. Many folks go for cheaper as they are so expensive, but remember, the OE pump made it this far.