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Synthetic Motor Oil

A friend of mine swears that synthetic motor oil is the way to go for his 1994 Saturn. He said the reason it has lasted as long as it has, i.e. 210,000 miles is because he used synthetic motor oil. Is this true? or is regular motor oil just as goo? Thanks!

An engine should last just as long using crude oil as it would if synthetic were used. If an owner paid all those extra dollars, of course he will crow about his results!

Syhthetic oil is claimed to have some advantages, but we have no evidence that, in practice, it really extends a engine’s lifespan.

The care you take of your car is the most important thing. I ran a 1984 Chevrolet Impala V8 for over 300,000 miles without synthetic; just normal oil. The engine at that mileage was still in nearly new condition, with 6 cylinders at 100% and the other two at 96% and 92% of new compression.

Your friend is no doubt concientious and maintained the Saturn by the book. That means changing oil on time, and flushing the cooling system on time to avoid overheating and head gasket failure, which was very common with this car.

The viscosity of the oil for the climate and driving conditions is far more important than whether the oil is synthetic or mineral. The owner’s manualwill tell you all this.

If you live in a climate of extreme heat or cold, synthetic oil is well worth the money. If you live in Seattle and don’t tow a trailer or drive extremely fast, it’s probably a waste of money.

The next time you ride in a taxi, ask the driver how many miles he has on the clock, then ask him if he uses synthetic oil. Chances are he won’t.

The only place I have ever seen CRUDE oil put in an engine was in Russia in an oil drilling camp. It did not last very long. You probably mean MINERAL OIL or “dyno oil”.

Our two Corollas (91 & 94) have all gone past 210K on regular oil. Proper and frequent oil changes seem to be the key, not necessarily synthetic. For us, oil changes every 5K miles did fine.

All my cars go high mileage, and it’s always been on dino. My Toyota pickup went 338,000 on dino…then it got totalled by an errant Hyundae. It still wasn’t burning oil.

By the way, I’m referring to over 40 years worth of vehicles. has a good primer on oil. I suggest a visit.

The answer to this question (which is debated hotly across the internet) is both simple and complex at the same time. In 1994 when your friend got this Saturn premium synthetic oil was far superior to conventional oil-no question. It was not really a big debate among the educated. Then as time passed conventional oil kept improving while synthetic stayed the same, or in some cases de-evolved.

What does this mean to you? Without getting into the engineering of all of this a premium synthetic oil will flow better at extreme low temperatures and have a higher flash point at extremely high temperatures. If you live in a radical climate (North Dakota) then synthetic can be a wise investment when it’s 30 below zero. In general it tolerates abuse slightly better than conventional oil. It can also reward you with ever so slightly higher gas mileage in part due to superior sealing in the combustion chamber near the upper portion of the piston-a result of a higher heat tolerance and less burn off.

So I suppose to answer your question-he’s not incorrect, but it didn’t play a massive role. More important is oil change interval and use of the correct grade of oil. Also using a good quality filter never hurts.

Synthetic oil is better, but regular dyno oil is pretty good too. I’ve had a couple of vehicles last over 250k miles on regular dyno oil.

Synthetic oil is better, but unless your car requires it, in most cases it is a waste of money. If your car requires synthetic oil, it will say so in the owner’s manual.

Synthetic is better in several ways over regular oil, but if your owner’s manuals does not specify it, and if you follow the oil change schedule that applies to your driving, then it makes little or no difference to the life of your car.

Very very few people sell or dump a car due to oil related or worn out engines unless there was a good reason other than the type of oil used. Usually they did some thing stupid like not following the recommended maintenance procedures or more likely, just got tired of the old car and traded it.

I’ll simply list my own experience with using full-synthetic oil (Mobil-1) When I bought my car about 8 years ago with over 100,000 miles on it, it would use about 2 quarts between oil changes at 3,000 miles. When I switched to Mobil-1, I immediately noticed the car was idling and running smoother (I’ll admit it is subjective) I change my oil at 6,000+ miles using full-synthetic. The oil stays cleaner and clearer, and I rarely use more than a quart between 6,000 mile oil changes, although my car has almost a quarter-million miles on it now. The oil costs about twice as much, but I can go twice as long. I notice no sludge whatsoever under the oil cap. Personally I’d never switch back to conventional oil.

I should also mention that when the outside temperature is 10 degrees or below, my car cranks more briskly and seems a lot happier on startup than when using conventional oil.