nattieman00 Posted February 18, 2008 Posted February 18, 2008 Has anyone used a fuel max in a 2006 gmc sierra 5.3. Has it helped with fuel like they say it will. Up to 4MPG??
lerbud Posted February 18, 2008 Posted February 18, 2008 get a custom tune. you can get 2 plus mpg and a lot more horsepower........
Recommended Posts
Archived
This topic is now archived and is closed to further replies.