transmission or gears for better highway driving

[Tomcat71]

LS is nothing.....

 

[DRAGGIN95]

Sure thing!

 

[vipergtrdj]

The power difference from a Vortec 350 to a 6.0 is amazing, you would love it!

I have been reading up on the swap some. figured I would throw out that on a 140mile round trip over Thanksgiving my 5.7TBI got 20mpg. I was impressed. That was mixed driving - mostly back roads, up hill, downhill, S-turns, averaged around 55-60mph. None of it was straight highway driving so the mph varied. So I am pretty impressed. Just hope once I replace my O2 sensor, it will be either the same, or better.....hopefully not worse.