I was told by my mechanic that my car, 6 years old, 115,000km mileage now, are not encourage to use full-sync engine oil, he asked me to use semi or mineral. He say full-sycn is for new car.

How true is this statement?

Well..That is probably because the Fully Sync's viscosity is too low for an aged/old engine..
As far as I know, the reason is your old engine's internal is worn and there is more clearance between parts and parts especially the piston rings etc.
So if you use Fully sync, due to the low viscosity of it, the oil will leak into the combustion chamber and thus, your engine will "makan" the engine oil while it's running.

That's all I know..Though there is a contradicting part with me..
I've also learn that the Semi-Sync's viscosity is not consistent...
At high working temperature, the viscosity of it will become thinner..more thinner than Fully-Sync...
Now I'm confused as well -.-


This post has been edited by awyongcarl: Jul 11 2008, 12:35 AM

u can always give a try~
if ur engine oil goes down/depleted like let say from full till half or min level in 30-50days
then tat's how u know d answer~

i used to use full synthetic on my year 89 engine without problems... at the time the engine was already 13 years old.

had it changed every 10,000km. engine was good and engine was smooth. never had a single issue.

the engine also had lots of high revving fun on drags and on track. the engine was a B16A though.

old or new car, after overhaul engine can use full syn lor...

nah, just clean and overhaul, you can use fully syn dy. If your engine was put to rough usage before, what eva oil also same...

i'm using fully synthetics in my 12 year old 4G15P
200k mileage, never overhaul before
and im using weight 30 oil, all the mechanic went o.O when i told them i only use weight 30 oil(according to them, weight 30 oil is only for kancits, kelisaps and kanaries)

my car 4yrs with 140,000km on the road has been using semi all these while... trying to change to fully this coming service. DUnno is a wise choice a not?

yes...need to overhaul 1st...

TS...u can juz flush the engine once then try the fully-syn out....
cuz the fully syn oil was so 'thin' it might burn engine oil if ur piston rings worn out....so do check the engine oil level oftenly when u try fully-syn....

just simple fast explanation :

- synthetic oil is good, it lubricates better bcoz its particles are smaller (than mineral oils), thus covering the engine parts more completely

-new car should use synthetic as the lubrication will be better

-old cars should not use synthetic oil. u gonna waste yr $. why? bcoz old cars, the engine parts are worn, synthetic oil, its particles being tinier will seep thru the worn out parts into the combustion chamber and be burnt or worse scenario leaked away.tat is why old car tat uses synthetic usually have to top up before the month ends

new car someday will bcome old car rite? so how?

overhaul...

so its juz a matter of time rite? using semi-syn compare to fully syn is ur car will overhaul earlier than the one using fully syn rite?

yes...thts the best bet...

i'm using fully-synthetic weight 30 on my 13 year old engine as well.

engine cc???

I'm running on full syn with an engine that has done 116K km in the last 5 years. It is wrong to say that old engines cannot use full syn. The advise is that if an old engine and has never used full syn before, then it is not advisable to change and it might dislodge the old mineral oil from the seals and cause a slight leakage.

So the advise here is, if the car has never used full syn for a long time, then it is not advisable to change.

This post has been edited by sleepwalker: Jul 11 2008, 02:49 PM

but between fully syn n semi syn, is there a huge diff? coz my car is juz around 30k, so i think still can use fully syn if i wan

This post has been edited by Ultima: Jul 11 2008, 02:55 PM

of coz lots of difrnt...like toyota and merc..