I am a new member my name is Phil and I drive an 03 2500 HD LS 6.0 Silverado

My question is what can I do to get better fuel economy? I have changed the cold air intake and the exhaust. That gave me about 3.5 to 4 MPG Is there anything more I can do? I tow a travel trailor at times and I get between 8 & 9 The best I have gotten is 12.5 not towing. It seems the different brands of fuel give you different results.

 

Are you using an ethenol blend? That will give you less mpg than pure gasoline.