Missing an oil change?

[Wade Lippman]

I have a 2011 Subaru Impreza. Last June I gave it to my son as a college graduation present. The last oil change was in February at 29,000 miles. The interval is every 7.5 months or 7,500 miles. I didn't drive much so I did the 7.5 month changes.
It now has 38,000 miles, so it is 1,500 miles past due.

How critical is that? Will it lead to a catastrophic failure in the next few miles, reduce the engine life a bit; or something else.
Serious, I don't know. I always do my oil changes religiously and never have a problem.

He is a good kid, but geez, when I was 23 I did my oil changes. He goes to graduate school, student teaches, and has two part time jobs coaching crew; he says he knew he was past due, but just didn't have time. I explained that he had to find time; but no one had to explain that to me.

[Bert Kemp]

I wouldn't worry to much just change the oil and all will be fine.

[Kev Williams]

Not critical.
Big diesels, which work much harder than any car ever will, and use plain old non-synthetic 15w-40 oil have recommended 15,000 mile changes.

You're fine.

[Ken Fitzgerald]

Just change the oil and the filter. Things should be fine.

[Mike Circo]

If like most Subaru's the oil is full synthetic, you haven't even reached it's EOL. Although Subaru indicates 7500 miles for a change on full synthetic, the oil manufacturers often say 10,000 to as much as 15k miles. So no worries.

[Matt Day]

It's a Subaru, so it's hard to kill. You'll be fine.

[Wade Lippman]

Thanks for the reassurance. My son isn't likely to repeat that mistake.

No, the oil is regular. They went to more refined engine in 2012; that is probably synthetic.

[Jim Becker]

No worries about catastrophic failure from "going over" a few miles! It's the folks who don't bother to every change it that suffer that kind of consequence unless there's a defect somewhere.

[Chris Padilla]

Old oil is better than low to no oil, Wade! LOL!

With the new synthetics on the market, oil change intervals are longer now than ever. I'm old school and always thought every 5k miles. Now many car manufacturers say that 15k is good. BMW says that. Even with that, I still changed mine at every 7.5k. Now BMW has oil changes built into the price of the car for the first 4 years so I just take it in when the car TELLS me it needs one! How about that?!

[George Bokros]

I use Motorcraft Synthetic Blend and still change every 6 months or 2,500 to 3,000 miles which ever comes first. My dealer recommends every six months or 5K miles with the Motorcraft Synthetic blend.

I know I am old school but keeping the lubrication system clean is a good thing. Oils are better but oil filter construction hasn't changed.

[Bob Turkovich]

Following the oil manufacturers recommendation (instead of the vehicle manufacturer) is not a good practice.

While there is more than one factor that can affect oil life, the major factor is time-at-temperature. Late model vehicles that have oil life monitors use a history of how much time you spend at specific oil temperatures compared to a histogram stored in the engine control module. (There is usually a prescribed do-not-exceed time/mileage limit as well.) There is no way the oil manufacturers can control that or know what it is from vehicle/engine model to model.

Off the top of my head, the main factors that can affect vehicle-to-vehicle oil temperatures are:

Does the vehicle get driven frequently in relatively high ambient temperature? (If he's living in upstate NY, probably not.)
Does the vehicle get used for a lot of trailer towing?
Does the vehicle spent a lot of time on severe grades? (Depends on where you are...)
Does he perform a lot of heavy accelerations? (Drag racing...)

Regardless, he shouldn't wait too much longer before getting it changed. If the answer to all four of the above is no, it is probably high liklihood that there has been no damage.

The same logic applies to transmission fluid as well. There has been a lot of discussion about vehicles that promise lube-for life. With certain formulations that are out there today, if the vehicle manufacturer can keep the temperature low enough, you can get lube-for-life performance.

Note: If the dealer is quoting an even lower oil change interval than the vehicle manufacturer - walk away.

[Jim Becker]

With the new synthetics on the market, oil change intervals are longer now than ever. I'm old school and always thought every 5k miles. Now many car manufacturers say that 15k is good.

It's not just the oil that's allowing the longer intervals. The engines are also being designed to better support longer intervals, too. Some of those changes are physical and some are technology-based where the vehicle can more closely monitor actual oil condition to determine remaining effective life before replacement. Many schedules are written such that it's "when the vehicle hits x miles since the last change or when the vehicle's computer system tells you it needs changed; whichever comes first" for normal non-commercial driving.

[Bruce Wrenn]

And to think my wife was worried last week when she went 29 miles past oil change. All my vehicles observe 7500 mile oil changes. My 86 Nissian pickup had over 540K on it when it finally died. My 90 Honda civic has over 300K on it, but my 88 Montaro Sport.only has 257K on it. 94 Ford van has 205K. We drive them till the wheels fall off, put the wheels back on and drive them some more. Been running Walmart full synthetic for years. Three years ago, Ford van fuel pressure regulator lost it's diaphram, pumping about a gallon of gas into crankcase. Fixed regulator, changed oil And filter. 50 miles later did another oil and filter change. Still shows oil pressure in upper third of gauge. Had it been regular oil, bearings would have been wiped clean. Not only has oil changed, but fuel injection stops gasoline flow as soon as power is shut off, thus preventing cylinder walls from being washed dry of oil. My theory is all vehicles drive better when they aren't dragging around a payment book!

[Brian Elfert]

Not critical.
Big diesels, which work much harder than any car ever will, and use plain old non-synthetic 15w-40 oil have recommended 15,000 mile changes.

Big diesel engines also usually have 40 or more quarts of oil which helps them get those longer intervals. I certainly wouldn't use the fact that some diesel engines have very long oil change intervals to justify going over factory recommended intervals on a gas engine.

I wouldn't sweat going an extra 20% in miles on an oil change, but I wouldn't do it every time either. I have a 15 year old snow blower that for a variety of reasons has never had an oil change and still starts on the first pull. It had an oil leak that had to be fixed in a shop once so the oil may have been changed then.

[Russ Ellis]

I'm still on the 5,000mi oil change intervals. The tires need rotated anyhow.

I don't like going much beyond 5,000mi because my vehicle has a rather small oil filter. There is only so much that the thing can collect before it's no longer effective. I have yet to see this accurately accounted for in any oil life evaluations.

Going 1,500mi over isn't a big deal. Just get the oil and filter changed sooner than later.