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Oil

What is the real story on oil?? Is synthetic better than regular oil because of less viscosity breakdown and does it extend the oil’s life between changes? Are any brands superior e.g. Valvoline?? Is it best to stick with the same oil when changing oil?

You can switch between brands and even types (synthetic vs. dino vs. blend) to your hearts content as long as your owner’s manual doesn’t specify synthetic as required. Just look for the API and SAE badges.

For those of us whose owner’s manuals don’t specify synthetic, there have been numerous long threads debating the points of whether it’s truely better and whether you should ectend your oil change intervals because you’re using synthetic.

In over 40 years of car ownership I’ve never worn out an engine, some of them even after hundreds of thousands of miles, and I’ve used only dino. I make that to be 100% successful lubrication so far. How can anything improve on that? In the lab it might be proven better, but in the real world how could I justify the increased cost of synthetic? I can’t.

As to change frequencies, synthetic is subject to the same contaminants and dilution (from blowby) as dino. Since the goal is to prolong the life of the engine and not to prolong the life of the oil, does it really make sense to run the oil longer? Wouldn’t that tend to offset any advantage the dino might have? In my feeble mind it makes no sense to pay extra for synthetic and then run longer between changes.

Others will disagree.

Bobistheoilguy.com has plenty of info(too much) for the details on this. After spending a little time there besides boutique oils with limited distribution the best synthetic for price/availability/performance is Mobil 1.

Synthetic beyond the reasons you state is superior to dino in extreme temps both high and low. High it keeps it composure and in low temps does not thicken up and make your engine starts hard.

The catch 22 being, most engines in normal use NEVER get hot enough to reach the limits of mineral oil. Even high-speed cruising in the summer, oil temps generally stays below 230 degrees which is well within the safe operating range of mineral oil. Only when oil temperatures get over 300 degrees does mineral oil lose its composure.

To be fair, when temperatures dip below zero, it is INDEED a superior lubricant. In fact, that was why it was developed.

Is synthetic better than regular oil because of less viscosity breakdown

Yes, and for other reasons as well.

… and does it extend the oil’s life between changes?

No. You should continue with the recommended oil change intervals. If I had to go over the recommended changes I would want synthetic, but that does not mean it is a good idea.

Are any brands superior Yes, but frankly they are all very good and the differences are too small to really be a factor.

Is it best to stick with the same oil when changing oil?

No. It makes no difference with all modern oils.

Just make sure any oil you use meets the specifications established by the car’s manufacturer.

I buy the least expensive oil I can find that meets the requirements of my cars. This is usually the parts store brand. I don’t think one brand is “better” than another for a standard passenger car, and I change brands depending on price.

I also don’t think synthetic is worth the money unless your owner’s manual specifies its use.

I’ve been using discount oil for more than 30 years in all of my cars, regardless of mileage, without any oil-related problems.

Follow the recommended oil change interval in your owner’s manual, depending on how you drive your vehicle. Some people should follow the “severe service” schedule.

I also agree that BobIsTheOilGuy.com is the place for more, and better, information than you ever wanted to know about oil.

I too use the discount store brand…the Wally World brand…SuperTech.

Bob’s cool. www.carbibles.com is another good primer.

“Even high-speed cruising in the summer, oil temps generally stays below 230 degrees which is well within the safe operating range of mineral oil. Only when oil temperatures get over 300 degrees does mineral oil lose its composure.”

In many engines, oil does get well over 300 degrees, but not during cruising. It happens when the engine is shut down. A thin film of oil gets trapped on hot surfaces and has to absorb all the residual heat. Its not usually a lot of oil, but that small amount breaks down Each time you shut down, a little more oil breaks down, that is why it slowly turns brown, then black.

Synthetic doesn’t break down as fast so it lasts longer. In modern engines there are few other contaminants. They run so efficiently that there little if any fuel washdown and so well filtered that outside contaminants don’t get in.

The only question is economics. The oil costs more, but you don’t have to change it as frequently. There are a lot of factors in that equation besides just the cost of the oil. Some engines need the synthetic as they are prone to sludging up. Toyota v6’s are noted for this. Some manufacturers require it at least during the warrantee period.

I use Mobil 1 because I have a 2000 Toyota Camry with the V6. Otherwise, I’d be using dino oil. Dino is fine if you change your oil regularly within the specified intervals. Synthetic is more resistant to breakdown and sludging.