Fuel gauge sending unit.. is this normal?

[Mudfrog]

I've had bad fuel sending units before but they are typically very unreliable. The one in my Tahoe is not acting crazy but at the same time it does not seem right.

I should have a 26 gallon tank in my 2002, if I fill the tank up the gauge never quite makes it to full. My dad's 03 Avalanche will go past full for a while like most vehicles do.

My Low Fuel light will come on and a fill up only takes 17 gallons. Surely the low fuel light does not come on with 6 gallons to go? Is this a sign of a failing sending unit?

 

[jesse53]

Float arm sticks.. If I fill mine up it shows full for awhile then drops to empty, When I think Im low, Ive tapped on the tank w/ a hammer and it corrects itself. I run on about a half tank because that and below stays accurate, for some reason.

 

[Mudfrog]

I haven't had odd behavior like that though. Aside from it not actually reaching the Full mark it behaves correctly with the exception of the low fuel light coming on with almost 10 gallons still in the tank.

I am correct in thinking that the 2002 Tahoe's had a 26 gallon tank, right?