Chevy's 2.4L Ecotec Engine Uses an Excessive Amount of Oil

TL;DR

A series of unfortunate design decisions allow oil to end up in the combustion chamber of the 2.4L Ecotec engine. And a less-than-impressive oil monitoring system doesn't do anything to warn owners about dangerously low oil levels until it's much too late.

An illustrated oil bottle pouring out a yellow-green oil.
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GM made updates to its 2.4L Ecotec engine for the 2010 model year[1] that opened multiple ways for oil to get sucked into the combustion chamber where it's burned into oblivion. As the crankcase's oil level drops owners experience bucking at low speeds, engine knocks and ticks, fouled-up spark plugs, and irreversible damage to critical components like the timing chain.

And it's all made worse by an oil level monitoring system that doesn't do a darn thing until it's too late.

There is good news, however, as multiple settlements have extended protections to certain owners. Let's take a look back at how we got here.

Design Changes Lead to Oil Leaks

GM switched to direct-injection for the 2.4L Ecotec engine in some 2010 models[1:1]. The new design relied heavily on low-tension oil control rings, spray jets, and a positive crankcase ventilation system to lower fricition, increase efficiency, and boost performance.

It didn't exactly go as planed.

Oil control rings that are too thin

Each piston has multiple control rings to maintain compression, transfer heat, and keep oil out of the combustion chamber. That last responsibility falls on the oil control ring which is found at the bottom of the control ring stack. As the piston moves up and down, the oil control ring scrapes oil off the cylinder walls and prevents it from exiting the crankcase.

GM opted to go with a thinner, low-tension oil ring for the 2.4L Ecotec engine.

But the oil control rings GM chose are way too thin and wear down quickly allowing gaps to form in the ring's coating. Those gaps allow oil to sneak past and burn up in the combustion chamber.

Spray jets overload the already weak rings

To make matters worse, the Ecotec engine uses oil cooling jets to reduce piston temperatures. Lower temeratures means less fricition. Less fricition means longer durability and increased performance.

A woman fails miserably at stopping a spray leak from a torn hose
Ecotec oil control rings when the jets start spraying

But the jets spray pressurized oil directly into the cylinders where frail oil rings are already struggling to keep oil in the crankcase. This allows even more oil than normal to sneak past and faulty or worn rings into the combustion chamber.

Faulty positive crankcase ventilation (PCV) system

And because that's not enough, it's widely believed that the Ecotec has a defect in its PCV system. PCV plays an important role in engine efficiency, as it draws gas out of the crankcase, sending it through the intake manifold and back into the combustion chamber where it can be used.

But the Ecotec's PCV may be vacuuming more than just gas vapors as it also allegedly pulls oil off the valve trains and into the intake systems where it gets burned off.

Service Bulletin #15285C

TSB 15285C was released in March of 2016 and offered a real breakthrough towards addressing this problem.

While previous bulletins only offered software updates to reduce the recommended oil change intervals, TSB 15285C acknowledged oil consumption as an issue for the 2.4L Ecotec LAF engine due to worn out piston rings.

"Some 2011 model year Chevrolet Equinox and GMC Terrain vehicles, equipped with a 2.4L engine, may exhibit excessive engine oil consumption (less than 2,000 miles per quart of engine oil), due to piston ring wear."

Special coverage adjustment increases protections for 2011-2012 Equinox owners

As complaints continued to pour in, GM offered a special coverage adjustment in May of 2016.

Originally for 2011 Equinox owners, the coverage eventually extended the warranty to 7.5 years / 120,000 miles for 2010-2012 owners. The coverage included any costs needed to replace the engine's 4 piston assemblues which is a time-consuming and expensive job.

A Series of Lawsuits

As you might imagine owners of all other model years with the same exact problem were less than thrilled.

In the 2018 calendar year, GM faced three class-action lawsuits that all essentially followed the same pattern.

Those suits were consolidated and settled in May of 2019. Although the settlement hit a snag before finally being approved by a judge in late 2019.

Learn more about the settlement details on CarComplaints.com.


  1. The LAF and LAE variants run from 2010 to 2017 and appear to have oil consumption problems. ↩︎ ↩︎

Affected Models

OK, Now What?

Maybe you've experienced this problem. Maybe you're concerned you will soon. Whatever the reason, here's a handful of things you can do to make sure it gets the attention it deserves.

  1. File Your Complaint

    CarComplaints.com is a free site dedicated to uncovering problem trends and informing owners about potential issues with their cars. Major class action law firms use this data when researching cases.

    Add a Complaint
  2. Notify CAS

    The Center for Auto Safety (CAS) is a pro-consumer organization that researches auto safety issues & often compels the US government to do the right thing through lobbying & lawsuits.

    Notify The CAS
  3. Report a Safety Concern

    The National Highway Traffic Safety Administration (NHTSA) is the US agency with the authority to conduct vehicle defect investigations & force recalls. Their focus is on safety-related issues.

    Report to NHTSA