I have a 2005 F-150 XLT 5.4 liter with a 3.73 rear end ratio and 9800 miles. I purchased it new in July 2005. It gets 18 mpg on the interstate, but only gets 8 mpg consistantly in town. I am really disappointed. Is this normal, or could I have a problem that can be fixed?

 

it's under warranty. take it back to the dealer to have it checked. they might have to reflash your PCM.

 

I've found if I jack-rabbit off the line my MPG goes down significantly.

 

Yep I agree

 

It was happened to me before we have same model (mine was Supercrew, you did'nt mentioned it) anyway, just bought back to the dealer and they replace something on my my fuel system (Injectors) and it was under warranty (brought last November). So it might have the same problem.