Good thread.

I have always had long oil change intervals.


I'm currently on 15k on semi 10-40 intervals. My car is primarily highway miles.

Nice to know there are fellow kakis pushing semisyn 10W40 to 15k km OCI.
Btw, may I know your engine oil specs/brand and car specs please ?

I used variety of Brands

Castrol Magnatec
Shell Helix
Total Quartz

Or what other flavours I can find from Tesco when on sale.


I'm doing 15k OIC on my 2009 Hyundai Matrix with 200k ++ KM. I do 50k a year on mostly highway. About 4K a month, so its a 3 month interval. Filter is original Kia/Hyundai/Mitsu

Wow, with 50k a year you are a good candidate for 400k-600k km mileage car in time.
Highway miles are in a way easy on oils, in particular when oil viscosity grade is thick enough as like a xW40 in our local ambients.
I believe 15k OCI for Euro oil in 2009 Hyundai Matrix should be ok, but I would exercise caution on non-Euro oil with close monitoring.
Lately 10W40 semisyn Euro oils in Castrol Magnatec and Total Quartz 7000 are hard to come by, but fortunately Helix 7 Euro oil is still easily available.

There are some of my colleagues keep changing at 5k km even on fully synthetic.

Kinda waste.

I know them as a car guy.

That's typical 'fear' of the unknown ...

Can't really blame regular consumers as pretty much no one knows about used oil analysis.

And even if they do know about it, the price for such a service locally is just damn insane expensive.

Attach herewith the price that i queried last year.

That's real crazy pricings, but their target customers are industrial/fleet users by playing on their 'fears' as what gomen does to general citizens.

There is a member here Alcyon does it far cheaper incurring RM200+ by sending sample to Blackstone Lab usa.

I'd done UOA FOC from Petronas and Caltex for specific occassions and I don't subscribe to paid services by OEM's.

Hence my playing around with Blotter Spot Tests which costs me zero sen.

This post has been edited by zeng: Dec 9 2017, 10:33 AM

That's why better to just send BSL

Yeap true, sending it to Blackstone is much more cost effective.

But for 200+, unless the car owner is overly curious, the most logical thing is to go down the hyper market and grab the best fully synthetic oil, drive it to the nearest mechanic to get it drained together with a filter change, and likely can still emerge with some spare change out of RM200.

Well, for the fun of it and curiosity sake, 200+ for Blackstone is actually a good deal.

actually, 100+ if you use snail mail (28usd, back to 25 old price if you order 6 bulks)
200+ is poslaju

Tech Plus (Aeon Big) Full Synthetics 5W40
5200 km in 2007 Myvi 1.3L K3VE
48 hr Blotter
..frequent short trips <11 km

Yeah, 15K for me is fine. Given 90% of all the mileage is highway relaxed cruising.

But the discounted oils from Tesco are hard to come by nowadays. When they have it on sale, I usually buy a carton, unless they have a sale limit.


My old satria had 400k kms. Before a premature timing belt failure chewed up the valves. Not have time to rebuild the head myself yet. So i bought this matrix 2nd hand to pile on the miles.
Considering 2nd hand korean cars ALL have had their odometers tempered with (so no idea about the true mileage), my Matrix would be probably be about 300K now.

There are car guys and there are "car guys"

I am a car guy and an ex-performance engine builder and mechanic.

I detest short term oil changes. It is wasteful and harms the environment. Unless you drive a super high performance car or one with extremely tight engine tolerances, or one that sees infrequent use, frequent short interval changes are not necessary.

The biggest problem engine oil faces is condensation and moisture build up in the crankcase if the car is not driven enough. The other is particulates and carbon build up. Oil doesn't really wear out. It gets contaminated.


A real car guy will know when the engine needs fresh oil.



I used to do frequent oil changes on my turbo car running highboost, only because I get so much blowby on boost that the engine oil gets contaminated easily. Even then, its 5000km intervals for "frequent".

Oh wow....wolf in sheep skin....really didn't expect someone like you to drive a matrix.

Is your matrix a sleeper?

72 hr Blotter.
No centre zone observed.



This post has been edited by zeng: Dec 14 2017, 12:46 PM

Off Topic. But the Matrix is very underrated and misunderstood car, mostly due to how it looks. FWIW, it was designed for the European market so it feels and drives like one of that era. It is underpowered though...which means you try to maintain momentum in the corners.

Handles very good for a car of that type. I will leave it at that.

This post has been edited by jaycee1: Dec 15 2017, 10:52 AM

I tried the test, not really sure how to interpret it

Engine : K20A
Oil : Liqui Moly Special Tec AA 5W-30 with Ceratec additive
Mileage : 11k +

Is it 1.8? There's a turbo kit you can buy for the G4GB engine

Thanks for upload.
Though the image is blur'ish, it looks like to me there is no signs of presence of centre zone (oil drop size of about 6-8 mm diameter) and absence of greying/darkish coloured patches (meaning insolubles, oxidation contaminants, combustion byproducts etc), which is good news.
Can you upload a clearer image preferably 48/72 hours after drop to confirm presence/absence of centre zone and greyish/darkish patches inside and outside of centre zone ?

All image is >72 hours

Lighting and camera not so good, but below is how it looks from further away.
Above single blot from a different engine, with what i can only assume is newer oil, not sure the mileage or oil used.

Bottom two blot from the same engine as previously.