When I take the gas tank cap off when I fill up.. it kinda does a "whishhhhh" sound as if pressure is being released... that's not good right..... so what's the deal?

 

That's normal, any car/truck/van has pressure in the gas tank, it's just from the gas sloshing around and evaporating. Read under the filler on any new vehicle, it says to remove cap slowly to vent pressure...

Jeff

 

if i drive my '85 gsl-se until it's almost empty, i mean REALLY empty.... when i turn the car off at the gas stn. the tank makes a high pitched 'whinning' noise like a bomb's going to go off or something! it whooshes sometimes like yours normally, but after it makes that other noise, when i take the cap off the pressure almost blows it out of my hand! i try not to let the tank get that low anymore