Originally Posted by 
Dave Severson
				 
			Don't think you'd get enough return on the investment, if that's your concern....  but then that's not real unusual when playing with a truck anyhow....  
the weight is the biggest hold back on the truck...  Only thing I've ever got any kind of decent mileage out of in these behemoth trucks is a diesel.  The diesels will really react to air flow improvements, bigger exhaust, and a chip...  I've got a V-10 laying in the corner, someday going to build a light little car to put it in and see what happens....
Anyway, pulling around that much mass, a couple mpg improvement is probably about the best you could hope for...  Changing all the lubes to synthetics would probably accomplish the same....