Is synthetic oil worth it?


#1

I have a 2003 PT Cruiser, 80K miles, my wife has a 2001 Cruiser, 90K miles.



We would like to keep these cars a long time, we believe in owning cars until they die.



Would synthetic oil help our cause or is it just hype?



TIA



Mike




#2

I would not be surprised if the owner’s manual specifies a synthetic. If so don’t use anything else.

A good synthetic will help any car’s engine reduce wear and that could lead to longer life. However as long as you use an oil meting the specifications in the owner’s it is likely you will never reach that point as your car will likely die or you will have sold it for reasons other that oil related issues long before you get there.

Modern engines and modern non-synthetic oils are very good.

#3

Questions such as yours attract a wide variation in opinions, chiefly because there is no clearcut answer, none that is universally accepted.

In summary, synthetic oil can be shown in the laboratory to have certain advantages under certain conditions, but those of us who use only natural oil in our cars seem to get just as many miles out of our engines.

I suppose that those who use only synthetic oil are adherents of the “can’t hurt, just might help” theory. So for only a few more bucks, why not?

P.S. – I’ve never tried synthetic oil. The natural stuff is good enough for me.


#4

Questions such as yours attract a wide variation in opinions, chiefly because there is no clearcut answer, none that is universally accepted.

In summary, synthetic oil can be shown in the laboratory to have certain advantages under certain conditions, but those of us who use only natural oil in our cars seem to get just as many miles out of our engines.

I suppose that those who use only synthetic oil are adherents of the “can’t hurt, just might help” theory. So for only a few more bucks, why not?

P.S. – I’ve never tried synthetic oil. The natural stuff is good enough for me. [quote]
It “can hurt” if I am spending extra money for no good reason and don’t have that money to spend on buying my next car.


#5

Unless your owner’s manual specifies synthetic, I don’t think there is a good reason to spend the extra money, regardless of mileage on the engine or anticipated length of ownership.

I have two cars, one with 70K miles and one with about 110K miles. I intend to keep both of these cars for many more years, and I use nothing but inexpensive standard motor oil in them. I’ve NEVER had an oil-related problem with an engine, regardless of mileage, in more than 35 years of driving.


#6

Which kind of oil does your owner’s manual specify? If it is synthetic and you have been getting your oil changed by the dealer, you will have been using synthetic all along.

If the manual doesn’t specify synthetic, you almost certainly have been using conventional mineral oil. If so, I wouldn’t go to the extra expense of switching to synthetic, especially since you already have so many miles on both cars.

Our current cars are a 1998 Subaru Legacy with 172k miles and a 1984 Mazda RX-7 with 186k miles. Both are running fine on mineral oil. My next car is likely to be an Infiniti G37. Its recommended oil is mineral, not synthetic.

German manufacturers like Audi, BMW, Porsche and Volkswagen do specify synthetic oil for their products. In them, I would only use synthetic.


#7

Synthetic oil has been around for about 25 years. While some mfrs specify its use, if your owner’s manual does not, then your engine, likely without a turbo, does not need it. For ordinary cars, no clear advantage to justify the use of more expensive synthetic has emerged and there has been plenty of time for that to happen.


#8

I have been trying to research this question and this is what I have concluded:

Your engine will not wear slower with synthetic oil compared to API grade SM oil if the oil change interval is short enough.

The use of synthetic oil allows for longer periods between oil changes.

The safe oil change intervals are 3000 miles for conventional oils and 6000 miles for synthetics. Most engines and most driving conditions will allow oil change intervals of 5000 miles for conventional oils and 7500 miles for synthetics. Even longer intervals are possible if the conditions are right.

The more your driving tends to be characterized as severe driving conditions (repeated short trips, extreme cold waether, trailer towing) the closer to the safe intervals your oil change interval should be.

The only way to know for sure if your oil change interval is ok is to send a sample of your used oil in for analysis. Ok - I know I have lost most Art history majors, and hotel and restaurant majors, and Marketing majors here. Sorry, I am a retired Engineer.

The economics of the choice between conventional and synthetics depends on your oil change interval, your cost for oil and filter, and how much the labor costs, or if you do it yourself - how much your time is worth.

Like many things in life, the choice is often not clear.

Lee

If you want to read more about it, you can look on the oil forums at


#9

Walmart has there own branded synthetic oil in five quarts jugs priced competitively with dino oil, thats what I use.


#10

Many cars run into the 200k-300k range using regular dino oil. Keep one thing in mind though. Your transmission or other expensive to fix item will fail long before your engine ever wears out.


#11

I personally owned a Ford van and drove it commercially, totalling 386,000 miles and sold it running well, never turning a tap on the engine… Other than tune-ups and oil changes, that is. It was serviced monthly at 6,000 to 7,000 miles with Havoline 10W40 oil and Motorcraft filters. I serviced a fleet of 142 vehicles and many surpassed the 300,000 mile mark on the original engine using Havoline 10W40 oil and the OE filter. I am looking forward to an oil that can surpass those numbers. And I don’t think that Havoline is superior to other quality oils. But I have remained loyal after all these years. I question the extremely thin synthetic oils ability to handle the stress of flat tappets and avoid it.


#12

I’m using super-tech synthetic from Wal-Mart now. I really liked the Castrol Syntec ads that aired when it first appeared. If you have a timing chain, synthetic oil could make it last longer. If it does what it is supposed to. If you have a timing belt, I don’t see synthetic helping all that much. There is something else; the synthetic is supposed to withstand higher temperatures, which could keep your oil rings from sludging up if you should encounter those temperatures due to a radiator leak or some other catastrophy.


#13

been using synthetics since 1990 with somewhat extended drains of 7500-15,000 depending on the driving habits, ie; short trips versus highway mileage etc and is the engine hard on oil, (subjective conclusion based on oil analysis, etc.)

Now, I use synthetic in cars that do not leak and I can go at least 5000 + miles between changes to be cost effective. On my leakers I use dino. If you drain every 3-5000 miles synthetic will make no difference in longevity. today, engines will long outlast the rest of the vehicle. times have changed oils and engines are much better then 10 years ago whent the 3000 mile change interval was the golden rule