To oil change on kilometres, or calendar?

[Deuce]

As we all know, the average service manual says "10,000km or yearly, whichever comes first"

But is this really appropriate for something that does low (a couple of hundred, or only a few thousand) per year?

I've never taken the calendar recommendation too seriously, and then stumbled across this short article today:

Motor Oil Age Doesn’t Matter as Much as Mileage: Study

An oil testing laboratory has found that the conventional wisdom of six-month oil changes might be a waste of your money.

www.thedrive.com

Discuss:

 

[Smitty]

depends.... 6 mths of short (under5, 10km) trips are harder on oils than long trips

in 6 months, if its all short trips and you have covered 2,000km of down the shops and back
I would change the oil

the difficult one is 6-7000kms travelled in 6 months (country and city kms) , do you wait until 10,000?
personally yes...

plenty others will say ... nope, wait until 10,000

 

[greenacc]

It's not really the age of the oil that matters, within reason. It's the amount of water, fuel, combustion products and any other contamination in the oil that matters most. How does it look and smell?

 

[gtrboyy]

Always said for weekenders 6 months or 5000kms whichever comes first even though most of us wouldn't rack that up.

Longer you own an old modified car usually less end up driving.

Although if driving a car regularly over decent distances 7500kms wont hurt it.

 

[shane_3800]

The oil companies all understate the performance of their oils.
This is not a rip off act it is so they can guarantee their product.

The only way to be certain is to oil test which is what I'm doing atm to check this my self, it's about $36 a test.

How do I know what the oil companies do? I've sat down and had talks with their engineers on trade nights and asked questions.

But as soon as you run an engine you introduce contaminants that slowly degrade the oil so time based servicing is important, as a rule of thumb never go over two years and you will be safe.

 

[Ginger Beer]

With high Km engines there is also wear to take into consideration, more so IRT blow by, more blow by more contaminants

Same same for builds that have looser piston/ring to bore tolerances on cold starts where more fuel and stuff from combustion, like water, pushes past the rings , then tighten up as it comes up in temp

Same same for lots of short drives where the oil temp isn't hot enough to cook off the water that is made during combustion

And then there's fuel type and quality, E85 is hell on oil, as is Australia's general quality of fuel compared to some other countries

My cars are 5k km or 6 months

Disclaimer: I enjoy servicing the cars

 

[NORTI]

I’m slack with the Senator now. It’s been roughly yearly for the last 5yrs or so. It does about 1,000kms a year. Beard looked at the oil last time it was on the hoist and questioned if I had just done a service. Nope. It’s just not getting driven enough to get dirty.

Other things here have a tighter schedule depending on its build and use. Towing, track etc.

The VK however wins for longest unserviced vehicle here. I think it’s been 10yrs since it was last driven. Hasn’t been serviced either

 

[Smitty]

The oil companies all understate the performance of their oils.
This is not a rip off act it is so they can guarantee their product.

The only way to be certain is to oil test which is what I'm doing atm to check this my self, it's about $36 a test.
.............................

true but....
the oil maybe good but if you have a lifter that is spalling or a valve spring etching
the retainer, you end up with metal in the oil
AND you really need to change the oil and filter soon and often!

One habit of mine .... comes from motorsport over the decades is cut open the filter when you change it
(as I did yesterday... no metal bits, fine filings or a even a silver sheen on the filter element = all good)

 

[Deuce]

true but....
the oil maybe good but if you have a lifter that is spalling or a valve spring etching
the retainer, you end up with metal in the oil
AND you really need to change the oil and filter soon and often!

One habit of mine .... comes from motorsport over the decades is cut open the filter when you change it
(as I did yesterday... no metal bits, fine filings or a even a silver sheen on the filter element = all good)

Yes.
I've thought about getting a filter cutter. It does no harm to check, but puts your mind at ease about condition.
Opening a filter without a proper cutter almost guarantees a bleeding hand or two.

 

[Smitty]

Yes.
I've thought about getting a filter cutter. It does no harm to check, but puts your mind at ease about condition.
Opening a filter without a proper cutter almost guarantees a bleeding hand or two.

yes...
and as for those who use a hacksaw to open a used oil filter to check for metal parts.....