2011 GMC Sierra 1500
Reviewed By Matthew H (GRAND COULEE, WA) Reviewed for a 2011 GMC Sierra —12/19/2014 5:26 AM
Range product works well. It was easy to install. The AFM was causing my truck to "learch" when stopped at slow speeds (engine shifting from 8 to 4 cyclinders). Also had a lot of burnt oil leaving black residue near the tailpipe. The common problems you see with the GMC FLEX Fuel design. This product fixed them all. I did loose 2 mpg 19to17. More instant power overall. Good product to purchase if you decide to keep the truck instead of sell or return for one without the AFM issues.
2009 Silverado 5.3L
Reviewed By Michael G (AMARILLO, TX) —12/14/2014 4:56 AM
I noticed an annoying exhaust note change when the AFM would kick in. The range device corrected that problem instantly. Product seems to well constructed of solid materials. I haven't had a chance to check any mileage changes but at this point I am satisfied to have the engine at full power. The truck is more responsive to the throttle.