Will using a synthetic oil reduce engine oil burning?

I have a 2000 corolla that burns oil. The issue is from the small oil return holes that get clogged easily from the use of Dino oils with a lower burn point. If I use the top of the line pennzoil synthetic oil, will this clean everything up and clear the sludge and carbon so I won’t burn as much oil? I’ve heard stories of this happening. My car takes 5w30. Should I go down to 0w20 or stay at 5w30? Also should I switch to synthetic for a oil change or two? Or should I just keep using the pennzoil Dino oil and save my money and not buy synthetic?

You have a 22 year old vehicle so oil usage is not uncommon. How much oil are you using ? Just try the synthetic and if it helps fine , if not then go back to regular . I would not use 0W20 in this old engine with who knows how many miles.

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Even from the factory. These cars 98-02 corollas burned. Many started after 100,000 miles but it is due to a design fault in the engine, not age. I would say my 22 year old corolla will last longer than most people’s new cars today. I can try synthetic and I won’t go to 0w20. I know pennzoil has a synthetic high mileage, would this just swell seals to prevent leaking? I know some of my oil loss is through a valve cover gasket leak

Nonsense .


I believe so. Come back in 15 years. I’ll still have this car. It’s 22 years old and getting close to 200,000 miles and I take 500 mile trips quite often in it. It never lets me down is the by far the most reliable vehicle I’ve owned. And I’ve owned a few 5-10 year old newer cars. Still on its original alternator, starter, engine, tranny, radiator. Everything. The only issue is it burns oil. I gutted the catalytic converter because of it and check my spark plugs. As long as I keep adding oil, there’s no issue with the car and I don’t believe there will be big issues with it in the distant future.

Can those holes be cleaned out once the valve cover is removed?

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So you are admitting to pollution of the air that we breath . Thanks a lot .


Unfortunately no. Once the holes are cleaned out, they get filled back up with gunk and carbon again. The only real fix is to buy the updated part Toyota sells with bigger holes. Or to bore out bigger holes. I have heard of stories of people always using high quality synthetic oils with a higher burn off rate and what this does is prevents the holes from getting by clogged in the first place. I’m hoping that I can change to synthetic and it will clear these holes. When I use marvel mystery oil, it slows the burning down by so much. I’m assuming that it is clearing these holes because MMO is basically a synthetic oil

Yes I am. Your welcome. Enjoy :blush:

You are missing the point of every one of my posts/reply’s. Me polluting is not the point I am trying to drive and the point that you keep bringing it up tells me that you have zero argument.

Believe me, some of these soft people nowadays need a little bit of car exhaust in their life. :laughing::laughing:

I have seen it work both ways. You might clean out some sludge and reduce the rate of burning or it might do nothing. A 0W30 or 5W30 Mobile 1 EP (gold bottle) would be my choice to start. I have also run the Mobile 1 0W40 European in engines wanting 5W30 with no issues. This seems to really clean stuff out as European cars have more stringent detergent levels for extended changes and turbos/diesels that can take this oil. This is really more of a “thick” 5W30 if you look at the viscosity numbers and a way to cheat on additives to keep the EPA and European makes happy in the US. This oil is not rated as fuel conserving.

I run the Mobile 1 EP gold bottle 0W20 in my lowly Mitsubishi Mirage with 70,000 miles. It calls for 0W20 so that is nothing strange for this engine. This isn’t a lot of miles but it burns no noticeable oil between changes. Also, when you open the cap to refill the oil, you can see inside the valve cover, top of the timing chain, etc. All the metal is shiny silver just as it was when the engine was brand new with no brown discoloration at all. That is kinda my test when looking at a used car to see how well the oil changes were taken care of. Remember this is the coolest part of the engine so the first part to gunk up.

Valve cover gaskets should be easy to change. Synthetic might cause one partly held together with sludge to start gushing as well. That happened with leaky oil cooler/filter lines on my 1997 Ford. They were just dripping oil with no noticeable loss but I went to synthetic and they started dumping a quart a day. I would change the gaskets before changing oil types.


You’re the type of hack I refuse to help with car problems.

If you brought your car to my shop and discovered you gutted the cat, I’d report you to feds and the state.



My car is burning oil. What do you expect me to do? Purchase a new cat every few years. Give me a break. My car that was in there was not even working. It stunk as much as it does now.

I would never go to your shop lol. I do all my work myself and never have a mechanic over charge me

Junk the car.



I’m hoping it will save me money in the long run because I won’t have to buy oil every few weeks. But I have also heard of synthetic causing leaks so it’s a hard choice

How about no. What a solution mr mechanic has for me

The market is crap, jobs underpay, everything is expensive. What makes you think I am going to junk my reliable car that gets 50mpg highway that I paid $1800 for a newer car that costs well beyond that. Oh yea the used car market is amazing rn. No thank you, I’d rather pollute

Wonderful car: oil burner, gross polluter, and it’ll be on the road another 200,000 miles…YIKES!


But hey I’ll have it for a long time more. So yea. Reliable and wonderful car

I think I would fix the valve cover gasket leak first. You might be able to change this yourself, especially on an older one. It is a KNOWN leak and you aren’t sure how much it is leaking.

I used to have several Geo Metros. The car was like working on a lawnmower with how simple they are. Almost all of them would develop a cam seal leak and the valve covers often leaked as well. There were sharp bends/corners where the valve cover went around the cam journals and timing seal. It is common for people to re-use the factory gasket and smear with with a thin film of red RTV after a good cleaning while putting a tiny dab of RTV at the sharp corners. They would never leak again, even with re-using the factory gasket.

The cam seal leak was due to a defect in the oil drainback on the cam journal behind the seal. The passage was offset and nearly blocked by the head. Another trick was to take a small metal file and give the slot for the drainback passage one nice swipe of the file so that it wasn’t blocked at the mating surface with the head. Any little dirt or sludge would block this as it came from the factory. Again, you would replace the seal (with a NEW one), put it all back together, and never have another leak after this fix. The red RTV is also easily removed if needed. Other colors such as black work great but can make future disassembly difficult, especially where there is a large mating surface such as a valve cover or oil pan…

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I have a push lawnmower I bought in 1992. The owner’s manual specified straight 30 weight heavy detergent oil. Several years ago it started really burning oil and put out blue smoke like I was fogging for mosquitoes. On a whim, I bought full synthetic 10W-30 under the house brand label at my local Rural King store. The oil was $2.69 a quart–$1 more than the straight 30 viscosity I had been using. The synthetic oil cut the oil consumption by 75%. I got three more seasons out of that mower.

I don’t think synwill help but slugging is from extending oil changes. You should be changing oil no more than 3000 miles or 6 months in my book. If they had a design flaw though, nothing will help so live with it. 0-20 is for new cars so forget it. Just imho.