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Synthetic oil vs. "real" oil

I am the original owner of a 1988 Nissan Pulsar that now has 195,000 miles. I’ve been using full synthetic oil for the last 2 oil changes (10,000 mi)but was recently told that synthetic oil “eats” the rings. I’d like to know what everyone thinks about using synthetics or high mileage oil.

I wonder if this myth started back in the 1950’s when detergent oil came on the market. When some cars were switched to detergent oil, the oil consumption increased dramatically. It happened to my dad when he switched to detergent oil in his 1949 Dodge. This may have perpetuated the myth today that switching from “real” oil to synthetic may cause a car to become an oil hog. I’ve used both regular oil and synthetic in my 2006 Chevrolet Uplander and I haven’t had any problems.

I run synthetic, regular and semi-synthetic (based on what’s on sale) and have had no engine performance or mechanical issues. Don’t expect any due to oil type, either…

I don’t believe it. But I’d use mineral oil if you change every 5000 miles. It’s well within the limits for mineral oil, and mineral oil is far less costly than synthetic. If you drive the car really hard, maybe you should use synthetic.

mineral oil? it’s a fun car to drive but we don’t drive it hard and it’s not used as a daily driver. We’re just trying to preserve the car and it’s mechanicals.

Synthetic comes from real oil that is chemically altered. The molecules are rearranged to make them better, more stable, etc. The oil doesn’t eat anything.

No one has been able to prove to me that synthetic oil is a better lubricant than mineral (petroleum) oil…It has a much broader temperature/viscosity range and it can hold more contaminants (blow-by) without smudging up but quality mineral oil simply excels as a lubricant…That’s one man’s opinion…

By contrast, synthetic oil is not distilled from crude oil. It is made through a chemical process known as the Fischer-Tropsch process, starting with raw materials like methane, carbon monoxide, and carbon dioxide. This process was developed by Germany in WWII, when that country’s access to crude oil was very limited.

You are good to go. Don’t worry. It is just another car myth. As with all good myths, there is a degree of truth in it, but it just does not mean anything.

A chemist you ain’t !
The process you mention has nothing to do with lube oil and synthetics are not made from carbon monoxide and carbon dioxide or methane .

Polyalphaolefins ,Diesters and Polyolesters are the ingredients of synthetic lube oils with the first two predominating .

Genex, Are You A Chemist By Vocation? We Need A Resident Chemist, Here.


Mineral oil means that it came out of the ground before refining.

Synthetic oil does not eat the rings. I have to wonder if that comment came from a quickie lube joint. I’m unfamiliar with Triedaq’a explanation, but it makes perfect sense. I’ve no doubt that there’s truth in it.

See for a good primer on oils.

And as long as your car does not require synthetic (see the owners’ manual) you can switch back and forth to your heart’s delight with no problem.

High mileage oil is a bit different. I recommend that you stick strictly to what your owners’ manual recommends unless you have a high mileage car AND it’s become an oil burner. In that case I’d suggest a higher base weight, and perhaps even trying a “flush” to decrud the rings and a new PCV valve as both may be contributors to oil consumption, rather than high mileage oil, but you can try high mileage oil if you’d like without risk.