Reviewed By RICHARD J (Parachute, CO) Reviewed for a 2005 GMC Savana —7/13/2014 9:25 PM
Big difference in power. I get 3 to 4 mpg more when using performance level.
Reviewed By Steve G (SHAWNEE, KS) Reviewed for a 2004 GMC S15 Pickup —6/13/2015 12:07 AM
I like the programmer, I wish it could do more to help or improve the gas mileage on my truck! 16 MPG before the installation, and 18 mpg after the installation.The increase was and is appreciated, I would like 24 or 25 MPG even better.I guess you can only do so much, with what you have to work with.