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2008 Toyota Camry - replace conventional with synthetic oil?

synthetic oil to replace conventional oil?

If you are looking for a prediction. Eventually, I suspect, synthetic oils will replace dinosaur oil in all new cars right from the factory.

I recommend it. I use nothing but synthetic oil. Used the same grade as regular oil. Same filters, too. I like Mobile 1 and Royal Purple synthetics.

While we are on the subject, I was taught by my high school auto shop teacher (43 years ago) that If you use conventional for over 20,000 miles, the rings will break down into the cylinders. Then carbon deposits will also become a part of the seal between rings and cylinder. If you then change to synthetic, it lubricates and cleans up the carbon which was part of the seal, creating loss of compression and burning More oil as more oil makes it past the rings. Kinda makes sense to me. Is this theory outdated or just a bunch of bunk? Or true?

We had synthetic oil 43 years ago in general use?

Motul introduced the first semi-synthetic motor oil in 1966 . Lubricants that have synthetic base stocks even lower than 30% but with high-performance additives consisting of esters can also be considered synthetic lubricants.

Had the same thought when I commented. But that’s why I was wondering if what I was taught might be outdated.

Back in 1953, my dad’s mechanic thought he should switch to detergent oil in his 1949 Dodge. That Dodge turned into an oil hog. Apparently, the detergent oil loosened up the carbon deposits on the oil control rings.
However, this was detergent oil and not synthetic oil. Since the 1960s, detergent oil has become the standard. Also, modern cars with fuel injection don’t build up the carbon deposits as the earlier carburetor equipped cars did.
For an experiment, I switched a lawnmower I bought in 1992 from heavy detergent 30 weight oil to 10W-30 full synthetic oil. This was in 2017. The oil consumption decreased 75% and I got two more seasons from the mower. At the end of this past season, the oil consumption increased, so I will have to replace the mower this year.
Unless one is using non-detergent oil in an engine, I don’t believe switching from non-synthetic heavy detergent to synthetic oil would increase oil consumption. My experience with the mower was the opposite.

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Before you waste money for no good reason, read this.

Tester

Just bunk. His description isn’t what happens. It may clean out all the crud left behind by conventional oil but the engine will seal back up.

I am a believer in synthetic oil myself. I wait until the sales/rebates and stock up so price is not an issue. I just simply pay ahead and pay the same or less as you would for a store brand conventional.

I tend to run Mobil 1 products in all my cars/trucks and Rotella T6 5W40 in all my outdoor power equipment. I sometimes pickup a used car or truck and always notice that the next oil change after going to synthetic gets dirty mighty quick. I have never had it really cause any major problems. I had leaky oil cooler lines on a truck. They were dripping before switching to synthetic but became a GUSHER after I switched. They needed to be replaced anyway and this just forced me to do it so I wasn’t upset.

I have had similar positive experiences with mowers as well. I have been given mowers or bought them very cheap for the use and abuse I give them on my farm. These mowers are often quite neglected before I get them. My most dramatic experiences have been with the Kohler Command single cylinders. These have hydraulic lifters so you notice them clacking loudly when the bleed down. Anyway, the old dogs I have come across have extremely noisy lifters and then you hit a tough patch of grass and the engine bogs down in a cloud of oil smoke!

I went to the Rotella T6, a Diesel rated synthetic. I noticed that the smoke and bogging down issues were gradually going away during the first mowing after the change. Then I noticed that the lifters were no longing clattering upon startup. I changed the oil and filter again as the fresh oil became dirty quite quickly and then the engines run like new. The second oil change doesn’t get dirty nearly as fast and I let it go a season before changing. Apparently the first change either cleans out all the sludge and/or deals with all the blowby as the rings free up.

I think the advice from 43 years ago is different from today. On the other hand I have come across some seriously neglected engines that come apart immediately after an oil change. I think that thick sludge is making up for worn clearance and new oil hastens the demise of the engine.