Synthetic oil or regular oil

I have been using regular oil in my vehicles for years. But some “car” friends have recommended I go to synthetic oil. Is this a good idea? Can I go from regular oil to synthetic oil without problems?

If regular oil has been working fine and is recommended by your owner’s manual, then you can continue to use regular without worry. has a great primer on oils. I suggest a visit.

I am another one who has been using Dino oil forever. I think the synthetic oil is just another way for the oil companies to vacuum your wallet. I’ve heard of many folks who change from dino to synthetic oil. Often oil leaks appear because the synthetic oil has smaller molecules(?). (Not sure about the reason).

Synthetic oils are designed mainly for EXTREME conditions; extreme heat, extreme cold, and extreme loads.

If you live in an area where it is nether very hot or very cold, and don’t tow a trailer, you are really wasting money with synthetics, unless the manufacturer specifies it (Vokswagen for example).

You achieve longer engine life by using good dino oil and changing it frequently, such as every 3000 miles, than by using expensive synthetic and thinking you can leave it in for 9000 miles.

For nomal use additive depletion determines oil change frequency, and synthetics have not much more aditives than dino oils.

I’ve never used synthetic oil and my cars seem to last as long as those that do. You can switch back and forth at will, if you choose to do so, but neither you nor your engine will notice any difference.

Part one. If the owner’s manual says to use synthetic, then YOU USE SYTHETIC. If it does not say, then it is up to you. It is not going to hurt. The old leak issue when changing is long gone. The current synthetics will not cause a problem. They may reduce wear a little, may increase mileage a little, power and noise may be a little better, but likely you will not be able to notice any of those changes.

I have a car with 445,000 miles on it . . I change the oil every 3,000 miles with dino . . . only work to the engine was valve stem seals. It is my belief that regular, frequent changes (with a filter change) will extend the life of your engine a great deal. But don’t forget about the rest of the car. Know where I got this info? OWNERS MANUAL! It lists all maintenance items with intervals which I followed religiously with this car . . . I used the severe service interval because I drive this car on short trips mose than I’d like, about 1/2 of the time, the rest is highway. Seems to have worked so far. I HAVE tried synthetic in a few engines, never experiencing any noticable difference (as Joseph suggested) and couldn’t live with the extended mileage/time change intervals. It bothered me so I just went back to dino. Rocketman

You can switch if you want, but unless your owner’s manual specifies synthetic there is no reason to spend the extra money. The oil you’ve been using up till now will continue to work long into the future.

Where synthetic really shines is at the extreme conditions. If you live in very harsh climates…where it gets extremely cold (below 0) or really hot (above 100), then synthetic is better then dyno…how much is the big question.

It’s not for everybody, but I liked the Castrol informercial that I saw years ago. I have used oil for enough years to say that running an engine on no oil is bad for it. None of my other engines ever stopped running or needed repairs related to oil. If you have an 85 Caddy or 87 Mazda truck with a four cylinder in it, you need straight 30 or straight 40 in the Summer and you could not use synthetic. I recommend one quart of Castrol Syntec in every dino oil change. What are my qualifications? Same as your friends. None.

Synthetics also extend the mileage between oil changes. This only saves money if you own a fleet by reducing the staff required to maintain it.

Yeah I’m with Rocketman. I’ve always used dino and changed at 3000. On our new car though I will be switching to Mobil 1 after break-in because it calls for 5W20 and want the extra protection from that light an oil. I think it is better and tried it in my old riding mower that was a bear to start in the winter and I could really tell the difference. The thing is that you still need to follow the dino oil change schedule, not the 10-15K that people like to follow with syn. IMHO.