Johnathan Goodwin walks to the back of his auto conversion shop in Wichita, Kan., and lifts up a gas nozzle connected to a huge cube-shaped container. He aims the nozzle at a clear plastic cup and squeezes the handle.
Out pours an orange-colored liquid that looks like a cross between iced tea and fruit punch.
"I always think when I'm pumping this stuff," said the 37-year-old, self-taught mechanic, "man, is this good for your motor?"
Watch David Kerley's report on Goodwin tonight on World News with Charles Gibson.
It better be. The orange stuff he's pumping is the key to his company's mission: converting the worst gas-gulping SUVs into cleaner, meaner machines.
"This is 100 percent canola oil, refined to biodiesel," Goodwin said.
His well-maintained shop is a bit like a showroom for that much-maligned symbol of environmental ruin: the Hummer.
Oddly, the brick walls of this shop that converts Hummers and other SUVs to run on cleaner alternative energies are dotted with nostalgic old signs for oil companies like Texaco and Mobil gas.
In one room, a bright yellow Hummer H-2 sits flanked by a silver H-1. Parked on the other side is a fire engine-red H-3 model owned by "Home Improvement" star Tim Allen. All the cars he shows off have been — or will be — converted by Goodwin and his team.
The silver H-1 — which Goodwin says gets 60 miles per gallon — has already been modified to run on biodiesel, diesel, vegetable oil, gasoline, ethanol, hydrogen, natural gas and propane.
"Pretty much anything that you want to put into it," said Goodwin, the owner of H-Line Conversions.
On a standard gasoline-to-biodiesel conversion, Goodwin starts by taking a new nine-mile-per-gallon Hummer and removing the original gas engine. In goes an off-the-shelf GM Duramax engine that runs on diesel fuel.
A few extra modifications and a tank full of biodiesel later, the Hummer — now boasting 500 horsepower and getting about 20 miles per gallon — is ready for the road.
"We double the fuel economy, we double the horsepower and we double the life expectancy of the drivetrain," Goodwin said.
It isn't cheap. A typical conversion costs about $35,000, allowing automakers to dismiss Goodwin as an experimenter who is only serving a narrow segment of wealthy car enthusiasts.
In response, he offers a couple of lower-cost options, including a fuel vaporizer for $1,000 that he says boosts fuel economy by 30 percent, and a $500 software download that reprograms diesel engines to get up to an additional seven miles per gallon.
His work has many wondering why the big automakers can't simply reconfigure their assembly lines to make their own cars run as efficiently as Goodwin does.
"I don't know why GM hasn't done it," says Goodwin, who figures he'd be out of business if they did. "But I can tell you that all the parts that I use for the conversion — 95 percent — are all GM parts. I'm not reinventing anything."
Automakers say bringing a new vehicle concept through the stages of design, testing, government certification and manufacturing typically takes eight or nine years. And they argue that simply building cars the way Goodwin does is not yet practical enough to be affordable to consumers.