Reviewed By peter v (Middletown, RI) Reviewed for a 2008 GMC Sierra —6/22/2015 3:24 AM
The AFM Disable is a great device. I've had it installed for roughly 1 month and it does exactly as is claims to, and no more. My base idle seems to be getting smoother and I don't miss the sometimes jerky transitions between 4 and 8 cylinders (especially noticeable if it occurs during a trans downshift. I'm not noticing a real impact in actual fuel mileage. I'd rather have a smoother running, longer lasting engine regardless.