Replaced the steel 16 wheels with factory 18 wheels, that are 14 pounds each heavier. The taller tire negates the extra drag at highway speeds.
Have a Superchips 3782 tuner to adjust speedo\shift points for tire upgrade & used mpg SAVER TUNE.
It is getting about 1.5 MPG better or close to 19 average, but that includes more highway driving.
Muffler heat shield rotted off....so that was 3 less pounds.
Run low on washer fluid.
I keep an eye for products but not many are to reduce overall weight.
I kept spare as it a little more cushion if we get re-ended.