Consumer Reports Reveals New Cars' Dirty Secret

Engines burn oil, but how much oil burn is normal is at the heart of a Consumer Reports study that examined nearly 500,000 new cars for how much oil they have to replace in their new car’s engine.

It’s a dirty, dirty business.

The report defined excessive oil consumption as adding more than one quart between recommended oil changes. The biggest offenders: BMW’s 4.8-liter and 4.4-liter twin turbocharged V8’s, Audi’s 2.0-liter turbo four and 3.0-liter V6. The report also said Subaru’s 2.0- and 2.5-liter fours and 3.6-liter flat six were lesser offenders.

According to Consumer Reports, the engines comprise only 2 percent of vehicles on the road, but that small sliver of the segment accounted for nearly 1.5 million cars. The offenders were particularly heinous in their oil consumption, as well — a new BMW 5-Series was 27 times more likely to need oil than an average new car.

Many new cars shouldn’t need additional oil between oil changes, the consumer group said, and oil consumption on vehicles with fewer than 100,000 miles should be the exception — not the rule.

Nonetheless, representatives from manufacturers such as BMW and Subaru said oil consumption for their engines isn’t out of the ordinary and could be dependent on temperature, driving style and transmission type.

The report highlighted the experience of one New York woman who said Subaru offered her $500 to offset the cost of new oil after she complained that her 2012 Impreza was burning too much.

Subaru’s Director of Communications Michael McHale said in a emailed statement that Subaru “doesn’t have a program in place but we do review each case on an individual basis.”

Out of court, some manufacturers have authorized repairing or even replacing an engine if it’s burning too much oil. In court, both Audi and Subaru are defendants in class-action suits regarding the problem.

Representatives from BMW did not immediately return requests for comment.

In some cases, automakers have settled the suits or extended powertrain warranties to cover any excessive oil consumption. In California, as part of a settlement, Toyota extended its powertrain warranties in some Camrys and Corollas to cover 10 years or 150,000 miles. Honda extended its warranty to 8 years on some of its 6-cylinder cars in 2013, after settling a class-action suit where hundreds complained about oil consumption.

BMW spokesman Hector Arellano-Belloc is quoted in the Consumer Reports story saying:

“BMW vehicles have long intervals between oil changes (10,000 miles). BMW engines (excluding the BMW M) may consume up to one quart of engine oil per 750 miles under certain driving conditions.”

Which sucks for me because my own personal 3 Series’ oil capacity is around 7 quarts — or about bone-dry halfway between regularly scheduled changes.

The report also underscores a small, but not insignificant, problem that manufacturers must do everything they can to combat the perception that cars are inefficient, environmentally irresponsible machines. Constantly pumping a car full of dead dinosaur juice may not help.