I don't know where this question belongs but have been wondering and no one seems to have the answer. When should you use synethic oil?

There really is no time when you should or should not use synthetic oil. IMO, unless you are racing and running the engine as hard as it will go all the time, synthetic oil is a waste of money.
In a vehicle that is used as a daily driver, you will see very little benefit from using synthetic oil.

Excpet less wear and tear on the motor and less oil change frequencies. I will never go back to dinosaur oil.

Agreed, I use Amsoil in my Taco and I can go over 7K miles between oil changes. I can probably go further, but I need to get an oil analysis done to know how much further I can go.

I would never go farther than 5,000 miles on any of my vehicles, regardless of what oil is in them.
Synthetic or not, oil still gets dirty and needs to be changed often to clean that dirt out of the engine.

Thanks everyone I wasn't sure I know it's time to change the oil and was thinking of switching over.

Every vehicle is different, and if you're thinking about switching, I'd suggest trying it out and keeping a close eye on your car. Try to notice any differences in performance, and check the oil yourself ever so often.

Actually, there is. You want to start using it at 30,000 miles (in my opinion) and under 100,000. If you have more than 100,000 then it won't do much good.



I disagree, it makes the engine last longer.




I agree but you still want to change the oil every 5,000 miles.

Secrecy,
You sound like my mechanic! He takes anything with my car personally. He long ago told me that my car was old enough to use the synthetic oil and that was what we were using from now on.

I got the distinct impression that I had no choice! Did you ever see the Seinfeld episode with Jerry and his car? THAT is my mechanic!

Thank your lucky stars for that mechanic! A good one who actually cares is tough to come by!

I know and I love Keith. But then his wife is a good friend of mine so it works out well. He can remember every single detail about my car but half the time he can't remember my name.

Oh, I'd love him! I want to find a Keith around here!

I run a full synthetic in all my vehicles. They have 300,000 kms on them. The filter gets changed every 5,000 km and the oil every 10K.

At -35 degrees, there is no oil superior to a full synthetic for engine starts. I also run sythetic gear oil for the tranny, transfer case, and differentials. The grease is also sythetic for nipple lube (on the truck...I know what you're thinking).

There was a huge debate on this subject in another sub-forum here. I could find out and post the link if anyone's interested.

I also use Duralube (and sometimes Slick50) which both use a teflon-based medium to coat the engine parts to aid in friction reduction. It's like wet ice on wet ice.

This combined with synthetic makes my vehicles capable of starting in the most nastiest of Canadian winters.

Oil additives won't do much. I say avoid them. An auto mechanic teacher says that he seen damages done by oil additives. Even Consumer Reports says that it is not any good.

Just stick with synthetic oil and you should be fine.

Would you happen to have a link or write-up on Slick50 or Duralube that talks about the risks and damage these products can do ? You mentioned Consumer Reports. That would be great.

Consumer Reports test those products out couple of years ago so I don't think I will be able to find it.

Maybe if you pay and join Consumer Reports online, you may be able to find it.

But I do some searching online for other articles about those oil additives.

You get to put the screws to the ragheads!!!!!!!!!GOD BLESS AMERICA