Fuel Pump noise after being off for 7hrs??

So last night at about 12 I went to get something our of my truck in the garage. While I was in there I could hear a noise. It sounded like the fuel pump right before I turn the truck on. I stuck my head under the back of the truck and sure enought it was coming from around the gas tank. I had not driven the truck since 5pm that night when I came home from work. I'm not sure if it was on the whole time or not. Is this normal that the fuel pump can just turn on 7 hours after I drove it last?

 

In the manual (pg. 130/2009 manual) it states after approximately 5 hrs after the engine is turned off, you may hear sound coming from under the vehicle for several minutes. It states this sound "is the sound of a fuel evaporation leakage check and, it does not indicate a malfunction".

This sounds like what you are experiencing. Hope this helps...

 

I've heard of this before, and the consensus was that the truck was venting some gasses of some sort.
It also apparently cycles the power for a second, because some who did the fog light mod had their lights come on 5 hours after they shut the truck off..

 

Awsome, I'm glad that it isn't anything I need to worry about. I just thought that it was weird that after 7 hours it was on.

 

WTF!?!?! Hahahahahaha...

 

Yeah one guy had his truck parked facing his neighbor's house and in the middle of the night they started shining into the guy's bedroom.

 

Hahaha...they probably thought he was an asshole.