I just bought a 96' F-150 with the 4.9 inline 6 in it. The truck has 2 gas tanks and the guy I bought the truck from said he never used the gas in the 2nd tank. I think the guy owned the truck for a little over 2 years so I'm guessing the gas in the tank is about that old as well. Also, the problem tank is only about a quarter full. My question is what should I do about this old gas? Is there an easy fix like adding fuel stabilizer, topping off the tank, and using it? Or would that cause other engine issues? Thanks in advance!

 

Yeah drop it and drain it and check the condition of the tank. I wouldn't chance it.

 

Unless the guy is somebody you know real well, odds are he never used it because there's a problem with it. Maybe not.
But if it's actually only all about 2 year old gas, I would just fill it up with premium and go.
Of course snaggletooth's suggestion has a lot of merit.