Hypermiling in a Hummer

[Mike Van]

About 3 years before buying my H3, I purchased a Prius and got very involved in hypermiling. In my 2003 Prius, my best milage was 76 mpg over a tank of gas. Now, I was on a road trip and a lot of that was downhill, but hey, it was still pretty high.

So, I got my H3 in 2006, and when I got it, I calculated that it had the best MPG and DPM (dollars per mile) of all other cars in its class. The MPG was pretty straightforward. But, the DPM was what really sold me. The fact that the H3 uses 87 octane gas, and most other vehicles in that class use high or medium octane gas, mean each tank is cheaper. Combined with the good mileage, I felt I was getting a pretty "green" vehicle.

Fast forward 5 years, and my initial thoughts were correct. Of all non-hybrid vehicles in the H3's class, the H3 has proven to be the "greenest" alternative.

Regarding hypermiling techniques, there are a couple "legal" ones that apply to the H3.

Pump and Glide

The pump and glide technique is where you accellerate to a speed just above the listed MPH and then coast. In hybrids like the Prius, while coasting you can effectively put the vehicle in neutral by slightly pressing the gas pedal. This results in a greatly decreased mechanical drag from the drive-train, and allows the glide to be longer. Additionally, hybrid's aerodynamics and more concentrated weight due to the large batteries result in long "glides". In practice, this is not the same with the H3. The pump-and-glide technique in the H3 results in a lower MPG than using the cruise control.

All of the Other "glide" techniques

As with the pump and glide, all of the glide techniques only work if your glide path is long, your vehicle is good aerodynamics and you can greatly reduce the mechanical drag by putting the vehicle in a quasi-neutral state. The only time a "glide" technique will improve your H3's fuel efficiency, is if it is done over a long decline in the road.

Don't use the Illegal Techniques

Listen, there's a reason we have the Darwin Awards, because stupid people do stupid things like the illegal hypermiling techniques. Just don't do them, and if you do, I welcome your addition to the Darwin Awards.

Techniques that Work

Early on in the hypermiling world, the simplest thing folks could do to improve thier mileage was to use cruise-control. Then, when the benefits of aerodynamics and having the power-train turn itself off automatically arose, the glide techniques started to dominate the hypermiling community. For us, the H3 drivers, the original message is the same, put your vehicle in cruise control and keep it there where it makes sense and is save.

Stay off the brakes. On non-hybrids, whenever you use the brakes you are wasting kinetic energy. Get used to stopping acceleration a couple hundred yards (meters) prior to a stop, and coast in. If someone gets all whiny and cuts you off, then hit the brakes.

Defeat the caterpillar. A major waste of gas in urban areas is the constant accelleration and decellaration required when you are in a traffic jam. Instead, try getting in the slow lane and settling on one speed. It should be slow enough that you can "coast" between decellarations, but fast enough that you can keep up with other vehicles. I usually try to stay about 200 yards at most from the next closest vehicle when trying this technique. Remember, the goal is to reduce accelleration and braking to as little as possible.

Steady. Find a mileage rate and stick to it, the slower the better. Do you really need to go 70 MPG? Try setting cruise control for 65 for a while. Your milage will improve and you'll get there in very nearly the same amount of time.