How often should I "really" change the oil?

The warranty and maintenance guide gives us two different guidelines, depending on the conditions we drive in.

My driving falls in the shorter trips / sometimes cold weather category with the 5000 mile guideline, so that's when I tend to change it. In my car, it is usually noticeably dark by then.

 

You don't change the oil because it looks dirty. You change the oil because it no longer protects the engine. Oil breaks down chemically and you can't see that. That "clean" oil is no longer lubricating as well and is no longer protecting the engines internal surfaces from corrosion. I don't understand the logic of saving a hundred dollars a year on a $20,000 + vehicle. Why not run the tires until they are bald and the plies are showing, that would easily save you a hundred dollars a year. Brakes are grinding? - ignore it for six months that'll save a hundred or more.

 

Times are achangin'

Many new vehicles are 10k intervals........
Some oil products are good/guaranteed for 15-20k miles. Off the top of my head...the newish Mobil 1 extended performance

Of course, this does not mean a person no longer needs to consistently check oil levels....

 

10k is fine, though as @ChapmanF notes short trips combined with cold weather are a factor.

Short runs without a complete warm-up cycle will allow water to accumulate in the oil sump. A hot extended run has the tendency to boil out any accumulated water. But if it's just 3 miles west in the morning and 3 miles east in the evening, you'll never get it hot enough to get this benefit. In that situation continue changing at 5k.

Factor this in and decide for yourself, and don't forget dipstick vigilance.

 

The question asked about stretching the oil change interval based only on the oil's color. I said this wasn't a rational way to judge the condition of the oil. If the oil's manufacturer says the oil is good for ten thousand miles then longer intervals are justified.

 

10k

 

The debate is never ending.
When I was young, first at car owning age, everyone used Dino-Oils and the accepted recommendation was every 3000 miles.

Now with higher quality synthetics and synthetic blends, that interval has been pushed out to various points.

My opinion with any and all vehicles however is to just follow the manufacturers recommendation.

In this case?
The OP is looking at extending the interval from 7K to 10K.
My feeling, opinion is...why?

IMO new vehicles are really amazingly maintenance free.
For much of a vehicles early life, it's tire rotations and oil changes.
And also IMO Oil Changes are relatively cheap. Whether you do them yourself or have someone else do it.

So for 3000 miles difference? Why risk it? Why not error on the side of an oil change being a little early as opposed to being a little late?

 

I find that hard to believe: did you pour some of the drained oil into a clean jar or something? If you try that I think you'll find it dark as ink, even after just 4000~5000 miles. That's not to say it's not still good, but just sayin'. Sure the dipstick film still looks pretty clear, but try the jar test.

Well that is the Toyota USA recommended interval. That said, I like the Canadian 3rd gen interval: 6 months or 8000 kms (5000 miles). For 2nd gen Prius Toyota USA recommended that too. Forr son's CX-5 Mazda Canada recommends that interval. It seems a common stance by the manufacturers, maybe playing it a bit safe.

 

Pay for a Used Oil Analysis and get the data needed to objectively answer your question. You might be surprised with the results or it might confirm the direction you are intending to go. Either way, it’ll help shape your choice.


iPhone ?

 

The oil was changed just before I acquired my '12 Prius C and it was so clean that it was hard to see where it was on the dipstick. About 700 miles later it's getting darker.
I plan to change my oil and filter at least once a year, maybe twice.
I have Castrol Edge 0w20 going into it in April. I only drive the car 4 to 5k miles a year.
If I was driving it 20k miles a year I'd change the oil 2x a year for sure.
10k mile oil change intervals should be fine as long as you run full synthetic.
I wouldn't try that with conventional oil.

 

My one year old, so nearly new, Prius C calls for 5,000 mile changes. So the times aren't changing for the Prius, and that's what the question was about.

 

Regardless of what the companies say, you can stick to or shorten the interval; it's your car.

 

interesting. i wonder why c gets 5k, and all other prius 10

 

Prius c has second gen engine if I'm not mistaken, and second gen oil change was 5K??

That your new ride?

 

John in Vermont....

Open your horizons.....Oil change intervals are also directly related to the oil quality.

You could do an oil change using oil purchased at the local Quicky Fill gas station for 2 bucks a quart. Would you still do it every 5k miles?

You can put in the Toyota recommended oil and do it at the Toyota recommended intervals.

You can also go to the opposite end of the spectrum with something like the extended performance M1 and extend the OCI even further.

 

Yeah, I think Prius c has a 1.5 liter engine, essentially the same engine that's in second gen Prius?

 

I agree with Vermont put the best oil you can buy in the car and replace it once a year.

I use Redline oil which is one of the best oils on the market and one of the few products on the market that you will actually feel and hear a difference
In the engine.

I also would not run the 20 weight oil they recommend by using Redline oil
There 30 weight is essentially a 40 weight oil which will help with oil loss and it had a zddp package also. 20 weight oil is for mileage but that makes that motor really noisey. Noise is wear. I see no mileage hit with Redline. 5-30 and engine is much quieter.

Buy 4 quarts of 5-30 Redline oil at Jeggs free ship and and see if you don’t agree.

I think your motor takes 3.6 quarts with new dry filter.