Help with weird vibrating whining sound?

[crawler dude12]

I was driving to school this morning and out of nowhere this very loud noise started. I think it's the fuel pump. It runs fine cold, but when it warms up it starts with the noise...
http://youtu.be/UrsS5A8Y65Y

It's kinda hard to hear with the video. My dad thought it was the t-case so we topped of it's fluid and went and drove it for a while. The noise is not as constant as it used to be but it still comes back every once In a while

 

[Kevin B.]

If you think it's the fuel pump it'll be easy to isolate. Next time it's making the noise, pop the access hatch under the rear passenger seat and have a listen. The fuel pump is right there, it'll be obvious.

 

[SAVAGE]

im pretty sure that is your fuel pump. like 100% sure. Many chevy fuel pumps that start to sound like that are what they sound like right before they die. It would be a very safe and a very good idea to throw on a new fuel filter also when you change your fuel pump. Not only to have a nice completely tuned up fuel system, but also a restrictive old fuel filter may have caused this pump to wear out prematurely.

(Also I dont mean to say that only chevy fuel pumps go out, it just seemes like they are the ones that are especially notorious for making that whining sound. Especially 93-99 with vortec 5.7)

 

[crawler dude12]

I haven't heard anything lately... I have a new filter but couldn't replace it cause I can't get the old one off... Might have to do it this weekend or something