Why is my 2010–2017 GMC Terrain 2.4 burning oil?

Short answer: The 2.4L four-cylinder in many Terrains wears its piston rings and starts burning oil, sometimes a quart every couple thousand miles or worse. GM's fix is new pistons and rings after an oil consumption test. Check your dipstick often until it's sorted, because running low can ruin the engine.

Symptom: The oil level drops between changes, the low oil or Oil Pressure Low – Stop Engine message appears, and sometimes a rattle or knock from the engine.

What to check first

1. Check the dipstick every fill-up. This is the most important step. Add oil as needed.
2. Ask the dealer for an oil consumption test. GM's bulletins have the dealer measure how much oil the engine uses. More than 1 quart per 2,000 miles qualifies for pistons and rings.
3. Ask about engine software and earlier parts. GM's bulletin says some early cars also need an updated fuel pump and timing parts checked when the rings are done.
4. Have real oil pressure tested if the warning is on. A low-oil-pressure message can also be a bad sender or worn bearings, so a gauge test is worth it.

Likely causes

1. Worn piston rings. GM says the top ring coating on these engines wears, which lets the oil rings stop working. New pistons and rings fix it; GM says the engine usually doesn't need replacing.
2. Fuel diluting the oil (early 2010–2011). GM ties some early ring wear to leaking high-pressure fuel pumps diluting the oil.
3. PCV or oil leaks. Worth ruling out before the big repair.

What it usually costs

Under GM's special coverage, the pistons and rings were free for eligible cars, but those coverages ran 7 years 6 months or 120,000 miles from the in-service date, so most Terrains are now outside them. I couldn't find a reliable source for the out-of-pocket price, so get a written quote, and if you're close to the limits, ask GM customer care about goodwill.

Is it safe to keep driving?

You can drive it short term only if you keep the oil full. If the Oil Pressure Low – Stop Engine message comes on, pull over and shut it off. Running these engines low on oil is how they end up needing a whole new engine.

DIY or shop?

Checking and adding oil is DIY. Pistons and rings are a big shop job.

Recalls, bulletins and complaints in plain words

• No safety recall for the oil burning, but GM ran special coverage programs (warranty extensions). If your car was covered, GM paid for pistons and rings.
• GM bulletin for 2011 Equinox/Terrain: coverage for 7 years 6 months or 120,000 miles.
• Special Coverage 16118 (2012 Equinox/Terrain) and N192291100 (2013 Equinox/Terrain): same idea, test the oil use, replace pistons and rings if it's over 1 quart per 2,000 miles.
• NHTSA complaints: 367 of 2,336 Terrain complaints from 2010–2017 mention oil consumption, burning oil, oil pressure or rings.

What owners report

• A 2011 Terrain owner on r/gmc called it "the dreaded oil burning issue", and the thread lines up with GM's bulletin about worn rings and low-oil warnings.
• The Terrain Forum thread on the 2.4L oil consumption update shares GM's explanation: new pistons and rings rather than a new engine, and the "zebra stripes" on the cylinder walls are just worn ring material.

My take

My advice as a former lube tech and inspector: if you're buying a 2.4 Terrain, pull the dipstick before the test drive. Low oil on a car that was supposedly just serviced tells you what you need to know.

Vehicle focus: 2010–2017 GMC Terrain with the 2.4L four-cylinder (the same engine is in the Equinox; the coverage letters list 2011–2013 models).

Safety / mechanic note

An oil pressure warning means stop the engine now. Running low on oil can destroy it. Verify with a mechanic.