Audi, BMW, Subaru called out for burning oil

Consumer Reports survey reveals excessive oil consumption reported by owners of newer vehicles

Published: July 4, 2015, 1:00 AM
Updated: October 11, 2021, 10:30 AM

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Anyone who was driving in “the good old days” is familiar with the process of having to add oil every so often (sometimes too often!) and having the gas-pump jockey asking to “check the oil” whenever you stopped in for a fuel fill-up.

Those days have mostly gone away with increased awareness of regular maintenance schedules (an prolonged oil-changed intervals thanks to engine refinement), but Consumer Reports is taking a few manufacturers to task over engines that are burning oil at an alarming rate in its latest Annual Auto Survey.

The survey questions owners of roughly one million vehicles over the past ten years and found “significant numbers of consumers have to add a quart of oil to their engines as frequently as every month,” according to a Consumer Reports story.

And although it may be normal for engines with 100,000 miles to burn “a little” oil, adding nearly a quart a month to engines in vehicles of 2010-14 model year vintage (CR focussed on roughly 500,000 such vehicles still under warranty) is unacceptable, says the publication.

It narrowed in on seven particular engines – Audi’s 2.0-litre turbocharged four-cylinder and 3.0 V6, BMW’s 4.8-litre V8 and twin-turbo 4.4 V8, and Subaru’s 2.0 and 2.5 “fours” and 3.6-litre six.

Those engines power the Audi A3, A4, A5, A6 and Q5; BMW’s X5 and 5, 6, and 7 Series; and the Subaru Forester, Impreza, Legacy and Outback. The worst offender, according to Consumer Reports was the V8-powered BMW 5 Series, with owners reporting oil consumption that was nearly 30 times worse than the average.

In their own defence, the manufacturers singled out say that oil consumption is a normal part of vehicle operation, with Subaru reportedly considering it acceptable for an engine to burn a quart of oil every 1,600 to 2,000 km. Audi and BMW reportedly consider it “reasonable” to go through a quart every 1,000 km or so.

However, Consumer Reports says that adding up to nine quarts of oil between oil changes is not reasonable when you consider the significant cost to ownership with the synthetics many of their engines require costing upwards of $9 per quart.

What’s even more troubling, adds the CR story, is that oil consumption increases as an engine ages, so today’s quart per month will likely increase with each successive year in service, and motorists aren’t always attentive to the need to constantly add oil to the engine as part of the upkeep routine.

A recent Consumer Reports survey revealed that 39 percent of vehicle owners never check their oil or have it checked and that could lead to costly engine repairs, especially if the wearing down happens more quickly than the owner anticipates.

And although the affected engines in the survey represent just about two percent of survey respondents, Consumer Reports suggests that any engine that burns oil excessively (which in this case represents about 1.5 million vehicles) should be repaired under warranty and urges automakers to not “shield themselves in the fine print of their owner’s manuals.”

Further, there have been civil action settlements against manufacturers in regards to excessive oil consumption.