Hmmm, now that you mentioned it, I think that I've read that somewhere...maybe there's a TSB about it...

 

Drive around with the bed off for a day or two. You'll be able to rule that out pretty quickly.

 

care to explain??

 

Big and long flat plastic gas tank expands/contracts with temperatures and pressure changes. After I park the truck and walk away, several minutes later it "pops" back into its relaxed shape. It's a normal condition, nothing to worry about.

For an experiment, put a plastic gas can with 4 gallons of gas in the sun, sealed shut. Watch it swell up. Loosen the cap, pressure vents, sides of the gas can relax. Same thing happens with your gas tank, but on a much larger scale.

 

hmm that does make sense. i just dont know why it would start doing it recently