Switching from conventional oil to synthetic oil for a car with high mileage?

Actually you would have to change it less because the synthetic is better in handling the extreme heat, the reason the website told you that was because oil companies do not like anything that tries to steal the competition. and synthetic oil is such as that an invention that oil companies just simply hate.

Synthetic oils have proven that they can last far longer than twice the recommended 3,000-mile oil change and still maintain their lubricant qualities.

what I have most often seen with the complications of switching over to synthetic is that synthetic is a ''cleaner'' oil and will have a lower density then conventional oil when cold. Over time your engine will build up small deposits and residue, sometimes what will happen is that the synthetic oil will wash away all of those deposits and you might encounter some leaking seals and such. I would say just keep using a good quality conventional oil like Mobil1 and it will be just fine.

Its safe to change over, just don't put conventional back in it.

Even a lot of the conventional high mileage oils now are as close to synthetic as you can get because of the additives in it.

Yes according to popular mechanics magazine you can switch back and forth from synthetic to conventional oil with no issues. However I would continue using the cheaper conventional in such an old car.

Just switch to synthetic at your next oil change, and keep using it every time you change the oil afterwards. I don't think you really need to change the oil more often; normally with synthetic you can go longer between oil changes.

Yes, it's safe to use synthetic oil. These days synthetic oil formulas are safe for seals and gaskets.

NOT really. I always do a mild SLUDGE REMOVAL treatment first. Reg oils make sludge and varnish on oil control rings and other palces. The cleaner tries to remove those sludgy coatings. IT MAY take until the second MOBIL ONE addition to get things back to normal again. I recommend using a PENNZOIL ULTRA first, then switch over. GOOD LUCK!!

You can switch to synthetic any time or mix them with any conventional oil any time you want.

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