Now if you don't want to go with an econo car.... you could always try....... a saturn Vue with the smallest engine and a 5 spd. Don't laugh they are chick car but atleast it gets 30 MPGs.

I generally get 20 MPGs out of my 4.0 2wd Ext. Cab 93 Ranger.

Be nice if you could just buy a cheap beater though and keep your truck.