Is it Normal for a New Car to Burn Oil ?

[Jim Becker]

Jim,

How do you like the Ascent? I've been surprised that I haven't seen more on the road.

As mentioned above we have a forester that uses a little oil and that fact alone has me put off from buying another Subaru. Otherwise it's a great car.

I've loved it for the entire 200 miles I've put on so far. But seriously, we're an all Subaru family now. The safety alone is a good thing...and Ascent is rated as one of the safest on the road at this point. Ascent is just finishing up its first year of production and is in high demand, but yes, there are not huge numbers on the road "yet". I'm not bothered by "normal quirks" of engines like oil use patterns as I noted above. Despite some perceptions, all engines "use" oil because of how the oil is used to lubricate moving parts. The degree is variable by engine type and by individual engine. And with today's longer maintenance windows because of improved lubricants and vastly improved engine designs, we might actually notice a little oil usage more that folks that stick to the very old "change at 3000 miles" schedule. Those engines are also "using" oil, but it's less apparent because it gets changed so soon. That all said, I say it again...excessive oil use isn't normal. But what constitutes excessive is not a concrete thing.

[Bob Glenn]

Neither of my Subarus (2011 and 2019) did that.

Cars have changed significantly in the last few years to tighter tolerances and thicker oils, but my 2016 Mazda never burned oil either.

Just read your article... It is dated 2015 and says that Subaru has been fixing the problem. Do they still say it is normal?

I believe that is THINNER oils, not thicker.

[Andrew Joiner]

Consumer Reports opinion means exactly nothing when it comes to determining what is and isn't normal. If the owner's manual says to expect to have to add oil then you don't have a legal leg to stand on. Having said that, I would be irritated too. I have owned a lot more new cars than most people because I worked for a car company and it was in my financial best interests. I never had a new car that used that much oil - even after 100,000 miles.

Thanks Art.
"oil consumption" in the owner's manual is like most new car manuals. It says "oil consumption" is normal under some driving conditions that we don't do. It doesn't specify any oil amounts or miles. So legally they may have an out.

[Andrew Joiner]

Andrew,

Our forester burns a little oil too. From what I've gathered the rings don't always seat properly which leads to more than normal blow-by.

The issue is suppose to be warrantied to 100000 miles. But where it gets dicey is that in order to determine if it's burning too much you have to take it to a dealer and request an oil burn test. They will then do an oil change and have you drive it a certain number of miles and then check the level. So you're basically trusting that they're honest.

We had the test done on ours at around 40-50k miles and they told us it passed.

My '96 Cummins with 420k doesn't burn a drop!

Thanks Jeff. What year is your Forester? We will get the oil burn test done. My Toyota with 80k on it doesn't burn a drop either.

Where did you find it to be warrantied to 100000 miles on this oil issue?
The powertrain is covered for 60k or 5 years on ours.

[Kev Williams]

Couple of thoughts here- Immediately after your oil changes, which is to say after the drive home from the shop and the engine has cooled, did you check the oil? It's entirely likely half or so of your missing oil was never there in the first place. Most shops use metered oil dispensers, and even if they're reasonably accurate you may not be getting a full pan of oil. For an accurate dipstick reading the engine must run at least a few minutes then allowed to rest long enough for all the oil to drain back into the pan.

The last 2 times I've had the oil changed in my beater '04 Chevy Venture, the next morning I've found the dipstick to say 1/2 quart low.

--newer engines not burning oil, another reason old engines used to wear out quickly: higher engine speeds. In the old days a typical car came with a 3 to 3.5 to 1 ratio differential gear and no overdrive, this meant running roughly 3000 rpm at 70mph freeway speeds. These days most cars will run 70 mph at 1500 rpm or less. I read once that an engine running @ 3000 rpm is using 40% of it's power output just to maintain its no-load speed! To that, add the resistance of pushing a 3500# car 70 mph, now the engine is really working hard! And needs a lot of fuel to do so! And, that extra fuel washes oil off the cylinder walls-- all that adds to accelerated wear. Today's engines are built tighter in the first place, computer controlled fuel control allows for making much more power at lower speeds, which greatly reduces power needed just to keep the motor running leaving more power to push the car- it all adds up to much improved fuel economy and engines that don't wear out!

'they don't build 'em like they used to!' -- yes, thankfully

[Wade Lippman]

I believe that is THINNER oils, not thicker.

Of course. Sorry.

[Rod Sheridan]

All engines burn oil, the cylinder walls have the oil burned off on every combustion cycle.

If the lubricant level isn’t falling, it’s due to fuel dilution, something an oil analysis will show.

The manufacturer will have a specification for fuel consumption which should be accurate....Regards, Rod

[Matt Day]

My ‘04 Forester burned about a quart ever 3-4k miles. It had about 130k miles on it when I sold it last year.

I’ve only done one oil change on my Ascent and noticed no loss (which means my oil pan was about full).

When I bought my Ascent back in August there was a preorder list and every Ascent that arrived at the dealership was spoken for. Basically they couldn’t be made quick enough for demand. It took a while before I started seeing them on the road. Today I saw 4 and was out for about 2 hours today.

[Ben Helmich]

Take it to the dealer, get it documented. Do it now. You never know how many warranties Subaru has on it and when they all expire. Not everything will be covered for 100K. They may do an oil consultation test. If so, follow their directions to the letter. They will likely have an oil consumption spec somewhere. For Ford, the spec used to be about 1qt per 1000 miles. That’s very generous, but you have to have some kind of spec to decide when to go into a motor and spend the manufacturer’s money on a repair. Oil consumption is uncommon but not unusual. Some cars just use oil. The question is always is it bad enough to spend thousands to make it go away. Make sure you’re using the proper weight oil. Other things can cause oil consumption also, including PCV systems, turbos, and oil leaks. How much oil consumption is “right” or what is “warrantable” may be two different things. I spent about 20yrs as a Ford service tech. I’ve been through this a few times as the tech.

[Andrew Joiner]

Take it to the dealer, get it documented. Do it now. You never know how many warranties Subaru has on it and when they all expire. Not everything will be covered for 100K. They may do an oil consultation test. If so, follow their directions to the letter. They will likely have an oil consumption spec somewhere. For Ford, the spec used to be about 1qt per 1000 miles. That’s very generous, but you have to have some kind of spec to decide when to go into a motor and spend the manufacturer’s money on a repair. Oil consumption is uncommon but not unusual. Some cars just use oil. The question is always is it bad enough to spend thousands to make it go away. Make sure you’re using the proper weight oil. Other things can cause oil consumption also, including PCV systems, turbos, and oil leaks. How much oil consumption is “right” or what is “warrantable” may be two different things. I spent about 20yrs as a Ford service tech. I’ve been through this a few times as the tech.

Thanks.
So your saying some new Fords would consume 1qt per 1000 miles and it was within the spec and not warrantied? What year was that?

[Mike Henderson]

Take it to the dealer, get it documented. Do it now. You never know how many warranties Subaru has on it and when they all expire. Not everything will be covered for 100K. They may do an oil consultation test. If so, follow their directions to the letter. They will likely have an oil consumption spec somewhere. For Ford, the spec used to be about 1qt per 1000 miles. That’s very generous, but you have to have some kind of spec to decide when to go into a motor and spend the manufacturer’s money on a repair. Oil consumption is uncommon but not unusual. Some cars just use oil. The question is always is it bad enough to spend thousands to make it go away. Make sure you’re using the proper weight oil. Other things can cause oil consumption also, including PCV systems, turbos, and oil leaks. How much oil consumption is “right” or what is “warrantable” may be two different things. I spent about 20yrs as a Ford service tech. I’ve been through this a few times as the tech.

I'd never accept the loss of one quart of oil every 1,000 miles on a car that I owned. The standard time between oil changes is now about 7,500 to 10,000 or 12,000 miles (depending on the type of oil). Assuming your engine had a capacity of four or five quarts of oil, you would be replacing the oil (by your additions) several times between oil changes. Even worse, if you forgot to check the oil on a very regular basis, you'd be getting an "oil light" on a regular basis, and it you didn't react to it pretty quickly, you could run the engine without oil.

It's been a long time since I owned a car that needed to have oil added between oil changes.

Mike

[Ben Helmich]

Andrew, it was maybe five years ago. My recollection of the spec may be off a little, but that’s the gist of it. And hardly any cars did it. And if they did, it was so slight you would never notice. My wife did have a Chrysler 300 that was close to that spec. It would be off the stick at oil change time. And I’d bet that most new car companies have similar specs. When a car comes in with that concern we would do an “oil consumption test.” Paint the drain plug and filter, top off the oil, let it sit for a while, scribe the dipstick at the oil level. Give it to the customer to drive for a certain mileage. Customer does not add oil or the test is invalid. Comes back in, top it off, do the math. Pass or fail. That’s how it was spelled out in the warranty guide book. But take yours in and get it documented on paper. If you’re going to be in this car for a long time you want it to be on Subaru’s dime if it needs a repair. Not on yours after the warranty is expired.

[Eric Danstrom]

Modern engines have looser piston rings to help with gas mileage. Specifying maximum of 1qt per 1000 miles is pretty standard amongst the various manufacturers. Some individual engines are worst than others within the same model year. If you're at the limit it's frustrating but there's little an owner can do.

[Robert Engel]

I have never heard of engines being designed to burn oil that's a new one on me. Even if this is true, what the poster is describing is way over the top

I have 4 vehicles ranging from 80K to 224K. I never have to add oil to any of them between changes. This includes an '06 F150(200k), a '97 Powerstroke (225K which I only change q 10K miles). My '08 Honda Element (160K) uses synthetic oil is also changed at 10K intervals and I never have to add oil between.

With that Subaru, I would be back to the dealership immediately and tell them you want them to explain why the engine is using oil. Quite simply, if its not leaking out, then the motor is consuming it, which means you need a new motor, IMO.

But at the very least, get it in your service record and start a personal record of oil consumption.

[andy bessette]

Excessive oil consumption is usually the result of improper engine break-in.