GM Faulty Mileage Claims Could Extend To 2 Million Vehicles

Last week, General Motors discovered a “clerical error” that led to the fuel economy numbers on several of its SUVs being inaccurate. The numbers printed on the window stickers are about 2 miles per gallon too high. GM said the error affected approximately 60,000 vehicles — the 2016 Buick Enclave, Chevrolet Traverse, and GMC Acadia. It instructed its dealers not to sell any of the affected vehicles until new labels could be printed and attached to  the vehicles. Just peel off the old stickers, put on the new ones, and then go ahead and sell ’em. Easy peasy.

GMC Acadia via GM

Maybe not. Consumer Reports has turned its attention to this matter and decided the problem may actually apply to over 2 million vehicles going all the way back to the Saturn Outlook, which is now out of production. CR points out the 2015 GMC Acadia is listed on the EPA website as getting 19 mpg combined — the exact same number previously listed on the 2016 window sticker that GM now says is inaccurate.

Consumer Reports wonders whether there are any significant changes in the powertrain between the 2015 Acadia and the 2016 Acadia that would make the newer vehicle less fuel efficient. It seriously doubts there is, since the Acadia and its corporate cousins, the Enclave and Traverse, are close to the end of their production cycle. CR speculates that any significant changes to the powertrain would be reserved for the next generation vehicles, which are due soon. And besides, it is unlikely that newer cars would have lower fuel economy ratings then the vehicles they are replacing.

GM fuel economy numbers
Source: EPA Website via Consumer Reports

When Consumer Reports asked General Motors whether the discrepancy extends to earlier models, a GM spokesman responded via email that the company, “…has checked and found no other models or model years were affected.” But CR is not content to let the matter rest there. It has reached out to the EPA for clarification and is waiting for a response.

The three models involved are all built on the same assembly line and use the same engine and transmission. In fact, but for exterior sheetmetal tweaks over the years, GM has been building the same vehicle for nearly a decade. In all, Consumer Reports says, since the Saturn Outlook went on sale in 2007 the company has sold nearly 2,000,000 of them.

The difference in fuel economy is only 2 miles per gallon, but CR estimates that costs consumers about $200 a year extra. Multiply that by 5 years — the average time the original owner keeps one of these vehicles — then multiply that by 2 million vehicles and “Houston, we have a problem. ”

“When asked about this directly, GM declined to give a specific answer regarding any substantial changes to these vehicles,” Consumer Reports says. In its own testing, CR says it often got about 3 miles per gallon less when evaluating these vehicles. While it seldom gets the fuel economy stated on the window sticker and reported by the EPA, the discrepancy is usually only one or two mpg.

For now, General Motors is sticking by its claim that the discrepancy only applies to 2016 models. But with Consumer Reports now nosing around, asking questions, one has to wonder how long it will be before GM changes its tune?

Source: Consumer Reports

Steve Hanley

Closely following the transition from internal combustion to electricity. Whether it's cars, trucks, ships, or airplanes, sustainability is the key. Please follow me on Google + and Twitter.