With high fuel prices on the minds of most Americans, GM adds a new level of service to OnStar’s monthly diagnostic e-mail that allows drivers to closely monitor conditions that can affect their fuel efficiency, including tire pressure and vehicle emissions.

OnStar Vehicle Diagnostics , an industry-first service available only from GM, collects valuable maintenance information on four of the vehicle’s key operating systems from hundreds of diagnostic checks and sends a personalized e-mail directly to the owner. The enhancements, being phased in throughout the remainder of 2006, will include tire pressure monitoring, E85 ethanol compatibility, enhanced vehicle emissions data and oil-life monitoring predictions to provide subscribers with real-time information on how they can help reduce gasoline consumption.

“OnStar increases its differentiation for GM vehicles, because OnStar Vehicle Diagnostics empowers subscribers to actively engage in vehicle ownership to help obtain greater fuel efficiency,” said OnStar President Chet Huber. “It’s a great extension of the safety, security and p eace of mind services that OnStar is known for and that subscribers use and value. When subscribers use the data provided it has tangible financial benefits.”

According to the U.S. Dept. of Energy, nearly four million gallons of gas are wasted each day nationwide for every one pound per square inch of tire under-inflation. That translates to more than $10 million per day, or $3.8 billion per year in wasted gas money 1.

New OnStar Vehicle Diagnostics offerings include:

• Tire Pressure Monitoring ­– Being rolled out in select models by the end of 2006 and across the majority of GM’s lineup throughout 2007, consumers will be notified of their vehicles’ current tire pressure and the manufacturer’s recommended tire pressure. In addition to the existing warning that in-vehicle tire-pressure monitors provide when a tire is significantly under-inflated, OnStar Vehicle Diagnostics will now notify drivers each month of the actual psi reading for each tire – allowing consumers to make small adjustments that can improve fuel efficiency. According to the U.S. Environmental Protection Agency, you can improve fuel economy by about 3 percent by keeping tires properly inflated (www.fueleconomy.gov).

• E85 Ethanol Compatibility – The e-mail also notifies drivers if their vehicles are E85 ethanol compatible and links owners to GM’s www.livegreengoyellow.com website, which links to the National Ethanol Vehicle Coalition’s (NEVC) handy E85 ethanol station on-line look-up tool. OnStar subscribers can search for E85 ethanol stations by using the NEVC’s look-up tool, or by simply pressing the blue OnStar button to receive directions to the nearest E85 ethanol station when driving.

• Enhanced Vehicle Emissions Data – The OnStar monthly diagnostic e-mail will now include detailed vehicle powertrain emissions data for additional peace of mind. Fixing an engine that has failed an emissions test may improve gas mileage by four percent, on average. That’s the equivalent of 12 cents per gallon 2.

• Enhanced Oil-life Monitoring – The OnStar Vehicle Diagnostics e-mail will predict the mileage at which the next oil change will be needed based on current driving patterns. Monitoring the percentage of remaining oil-life has been a part of OnStar Vehicle Diagnostics since its inception. This new enhancement allows drivers to know when an oil change is likely to be necessary. Following GM’s Oil-life System not only conserves resources, but helps save the time and money involved in scheduling unnecessary service. By following the GM Oil-Life System, it’s estimated that more than 100-million gallons of oil could be saved over the next five years from the millions of GM vehicles that already have this system.

OnStar Vehicle Diagnostics, which has had more than 1.6 million subscriber enrollments since its launch in September 2005, is exclusively for GM customers, and OnStar subscribers can enroll in the opt-in service at no additional cost by simply pressing their blue OnStar button and asking to be enrolled or visiting the OnStar Web site (www.onstar.com). OnStar Vehicle Diagnostics service can be activated on most 2004 model-year or newer OnStar-equipped GM vehicles that have GM’s Oil-Life System.