Review on Range Technology Active Management Disabler by Chad Black

First of all this blocker works and prevents the ecu from going down from eight to four cylinders. I just received it yesterday and couldn't properly measure the mpg difference. This stopped the rough downshifting and shaking. I am very happy with the product, just not with the price. You would think that for almost $200 you can choose from different modes. You know, sport mode, city, highway, etc. If you're complaining about the packaging and the operating instructions... please shut up. You didn't buy the box, and that's pretty stupid. Connect it to the diagnostic connector and drive the truck. It is really that easy. Advice. If the vehicle you are installing this on is not your daily driver; You can turn it off and keep it between uses. I plugged mine in before turning the key and the blue light on the unit started flashing. This tells me that it comes to power regardless of key position.