MKLEX

I have ES300 2000 (168k miles), just recantly i had replaced head gasket, timing belt, water pump. Before this job, I was using Mobil 1 syntetic and changing oil myself. After driving a car for a few weeks I notice the oil light coming up. I checked the level and it was low, so I added more oil. But then I realized that guy in garage put regular oil in the engine. I had to go to South Caroline and noticed oil level going low because oil light came up again.

Question to experts, can I change it back to syntetic and would this problem go away?

I really love this car, had it for 10 years and don't want to look for buyer because of burning oil.

brucelee1

iTrader: (2)

I would go back to syn and see what happens. It may not be the issue but it won't hurt in any event.

imherenow

hmm how did you know that it was synthetic oil in the first place..and also if there is an oil level is low then i think you might have a leak somewhere. i dont think its due to changing of oils. ( or maybe??).
Also from what i have read and heard once you use synthetic you should always stick with it.

285exp

I've heard of oils leaks starting after switching to synthetic, not the other way around. I doubt that switching back to synthetic will solve your problem. With the amount you're losing it would be pretty obvious if it was burning, and with the work you've recently had done it's more likely a leak. You'd do well to check the oil at every fillup until you get this resolved. Any time you get so low that it triggers the oil pressure light you're risking serious engine damage.

EEngineer

go back to synthetic and do a oil change after like maybe 1~2k miles just to flush out the regular oil again.

if you love the car, a little oil burning won't change anything, just top it up and change sparkplugs more often and do seafoam twice a year

MKLEX

i was using synthetic since i bought, but when mechanic did the major overhaul (head gasket) he had to drain the oil. So, he did and he put regular oil. Now i want to go back to synthetic, but don't know if it would be a problem. Car has 166k miles.

MrShim78

at that mileage would it make sense to stick to high mileage oil? might help seal /enforce sealing in the engine?

yeskay

check the owners manual for oil low light explanation.

285exp

Based on his original post, the low oil pressure light appears to be caused by low oil level. The question is where is it going.

ASG14

iTrader: (1)

As Prev stated, if you go to Syn oil the oil will leak more/burn more.

MKLEX

I had corrected the oil level by adding more "regular" oil, I don't know where it was going but now its OK.

Question: Can I switch to synthetic, or go for High Millage Oil?

hypervish

You can safely switch to synthetic motor oil.
And, I recommend doing so. Yes, modern day oils are much better. But...the 1MZ-fe is an engine which is extremely tough on oil, plus with it's small oil passages, in addition to the heads running hotter than other engines , it's a prime candidate for synthetic oil.

It's possible that the first time you run Synthetic the engine will consume a slight bit of oil, but on the second OCI the consumption should start to fade away.

MKLEX

well, thank you for educating me. I will switch back to synthetic next OCI. Should I flush it with a quart of synthetic first and then fill it up?

yeskay

oil level light not necessarily mean low oil as per the owners manual.

Hayk

iTrader: (1)

Switching from Regular to Synthetic does not promote leaks, that is all a load of crap. If you have a leak, it would have happened no matter what oil you used.