The device itself does not make any changes to your vehicle to improve fuel mileage. What it WILL do is show you how much fuel you are using based on your current driving habits. If you are willing to make changes to the way you drive based on the feedback this device provides, you might just experience some impressive increases in fuel economy.

Some vehicle models come from the factory with trip/mileage computers and for those vehicles this gauge MIGHT be redundant UNLESS you might also be interested in some of the other parameters this gauge might measure. One parameter in particular might be transmission temperature for those who tow and have automatic transmissions. Before you order, check the compatibility list to see if this device will function with your model vehicle for parameters in which you are interested.

I run this device on 2 different vehicles: 1) 1999 F250 Superduty with the 7.3l Powerstroke and 2) a 2004 Subaru Forester 2.5x with a 5sp manual transmission. To switch vehicles, engine displacement, size of the fuel tank and type of fuel have to be changed. Easy enough. The unit can give you bit of a headache setting it up, but after you’ve done it a few times, it really is a piece of cake. The tougher part can be setting up the XGauge, which allows you to program the device to read certain parameters that your OBDII computer might be monitoring. It is important to note that not all vehicles will have sensors installed that will provide the data to the Scanguage. Also, the commands provided just might not work on all vehicles. However, there should be few problems measuring parameters associated with fuel economy.

Most of our driving could be considered a rural 35 mile commute to town. The Subaru gets that duty. Prior to using the Scangauge, we were getting a solid 27-28 mpg on our Subaru. We were really kind of pleased with that. After hooking the Scangauge up and inputting some necessary information for our engine size, etc., it pretty much sustained what we already knew by calculating fuel consumption the old-fashioned way.

But then we started using the feedback from the Scangauge to adjust how much throttle we were applying under certain conditions. This is where it gets good. The feedback is instantaneous, so you don’t have to wait til the next fill-up to see how well you did. I had always believed that better fuel mileage could be obtained by shifting to a lower gear and not using as much throttle to go up a hill. The Scanguage showed me that was not always true and that it was sometimes best to stay in the taller gear as long as you don’t lug the engine.

I also decided that if there was no traffic bearing down on me, I would take A LOT longer to accelerate to reach highway speeds. The same went for slowing down. With no traffic behind me, I could take A LOT longer to DECELERATE making full use of engine compression to slow the vehicle down. Not only did our fuel economy improve to 31-32 mpg (14.3% better!), but I’m also still on the ORIGINAL brake pads…coming up on 135,000 miles!

I’ve done a LOT of driving in my time, much of it on the autobahns of Germany for 10 years and I know brakes. I still have 25% of the original brake pad material available which could conceivably put me at 168,000 miles before I do my first brake job on this car! Not only are the pads not wearing, but the discs look pretty good, too!

On the Powerstroke, results were even better. I was seeing an average of 13 mpg and that improved 23% to 16 mpg average for a local 12 mile round trips. On trips to the mountains I can get 18 mpg. Also, the Scangauge keeps me informed on my transmission fluid temperature when towing our 5th wheel trailer. I had also hoped that the Scangauge would provide information on torque at the torque converter (CTQ), Torque Converter Line Pressure (LPC), and Torque Converter Speed Ratio (SLP), but my truck does not have sensors for those parameters. I also learned with the gallons per hour (GPH) feature that this truck would burn .6+ GPH sitting at a stop light with the transmission in D. By shifting into N, consumption dropped to .43 GPH, a 31% savings. The display can be set to show 4 parameters at once.

In summary, after you drive with this device for a while, you are likely to change the way you drive. These changes can become so well ingrained that you might find that you will maintain your fuel economy, even after you remove the device and put it in another vehicle.

This device does a few other things as well, so look the literature over and remember to contact the company to see if it will work for your intended application if you intend to use for more than just monitoring fuel economy.

The Scangauge II isn’t for everybody. Folks who are not technically inclined might find it a bit laborious to set up and may not really be interested in the information it provides. Also, if you are already an experienced “hypermiler”, you might have already honed your driving skills to the point where you might not see much improvement in fuel economy. You might even already own one of these!

It is easy to fault this device for a somewhat laboriously techie setup, etc. But, as you use it, you begin to appreciate the thought that went into it. There is only so much you can put into a small package and still make this thing useful and fit in the cockpit of your car. But really, once it is setup, you really don’t have to fool with it anymore. Changing vehicles is simple. It has already paid for itself in the first 3 months. It gets 5 stars from me.