Synthetic oils, which is best?

Ijust got a 2004 pontiac montana an need to know ,of all the synthetic oil which is best for my mini van.

Do a search on this forum for this topic. It gets discussed quite often.

Unless your owner’s manual requires synthetic oil, or you’re operating it under one of the extreme conditions where synthetic excels (like -20 degree starts), you should really understand why you believe it’s worth paying the extra money for synthetic.

I don’t understand why you think you need synthetic oil in a minivan. However, it’s your money, so buy whichever brand you feel is best. I doubt there is a “bad” brand of synthetic oil.

Does your owner’s manual specify synthetic? If not you need to ask yourself why you want synthetic.

Synthetic will reduce engine wear, but when was the last time you saw a car junked or repaired due to oil related wear or failure?

Modern cars and oils are all so good, that the only thing you need to worry about is getting any oil that meets or exceeds the specifications for your car, and that your follow the recommendations for oil type and change intervals (don’t ignore severe operating conditions).

All else equal, synthetic will give you better mileage, but not enough to cover the additional cost of the synthetic.

Good Luck

The question is akin to saying what bottled water best quenches your thirst. They are all over the map in prices but they all do the same thing.

Conventional oil(akin to tap water in analogy above) does the same thing.

but, doesn’t it keep engines cleaner?

Doolie, I Choose Mobil-1 Extended Performance, But Regular Mobil-1 Is A Good Choice. Why Is That My Choice ?

Mobil has been manufacturing synthetic oil for a long time and is probably known world-wide and is recommended by some car manufacturer’s that specify synthetic oil for their cars.

The Advance Auto Parts store in the town near where I live puts it on sale almost every other month. 5 quarts of Mobil-1 with a Mobil-1 oil filter goes for about $30 when on sale. The Extended Performance version 5 quarts goes for $32 or $33 with filter.

When it goes on sale, I stock up with enough for 2 or 3 changes for each of our cars.

Most people responding to this site recommend that you still follow your car’s oil change intervals as described in your Owner’s Manual.

I have no way of assuring you that Mobil-1 is “best”, but it works for me because of reputation, price, and convenience, and the guys at Advance recycle my used oil!


but, doesn’t it keep engines cleaner?

If your car is designed for synthetic oil use (i.e. if it has a turbo), yes, it will. If you tow a lot, or haul heavy loads in hilly terrain, yes, it will. However, the single most important part of keeping the inner engine clean is changing the oil on time, which you should do whether or not you use synthetic oil.

It’s got how many miles on it?? If you want to obsess about Motor Oil and all its flavors, try

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Newer GM cars such as our 08 specify 5W-30 oil per GM spec 4718M. Mobil 1 5W-30 meets this requirement but there are other brands too. Our owner’s manual is very clear about this. Possibly this is an association with your 04 GM vehicle that will do.

We have a 2003 Olds Silhouette; identical engines. I change the oil when the oil monitor reads less than 15%, and usually less than 10% remaining. This is usually at 7000 miles after the last change. I use mineral oil, not synthetic oil. I also don’t burn any oil. It’s not only good for my van, it’s good for my wallet. It should work for you, too.

does anyone know how good Kendall GT1 is?

where can I find mineral oil?

Mineral oil is the stuff the oil companies get out of the ground and distill into motor oil, gasoline, and several other products. I call it mineral oil because it is mined like other minerals.

I’ve been using Mobil-1 for years and have been happy with it. Amsoil has a great reputation, or if you really want to spend a lot you can get Royal Purple. Unless you take your minivan to the track and autocross it, RP would probably be a big waste. You really should go to “” if you want to discuss what oil is best though.

I suggest Castrol or Mobil 1. Experimenting could take 60 years and involve three cars. Scientific process could take 60 cars and involve three years. It has been done with more cars for less time but the results were kind of “lost”. Lost to me, not to everybody. To me, I would say “not conclusive”.

My last oil change was with Motorcraft Synthetic Blend 5W20 with two quarts of Castrol Syntec 5W50. Ok Castorcraft 5W27. Why would anybody do that? Anybody wouldn’t do that but you could if you didn’t care to buy oil that wasn’t on sale. I can’t resist a chance to buy 7 quarts of Castrol on sale for $3.96 a quart and blend it with any known brand of whatever. I’m not afraid of the unknown; that one anyway.

I can’t tell what’s in those cans. To me; worrying about which oil to use among top brands is like worrying about leaving greasy marks on a brand new oil filter. I used a non-orange Fram filter too. Talk about challenging fate to swat me!

Use synthetics in a manner that makes them a zero cost or lower cost choice. Many synthetics aren’t promoted as extended drain oils. This isn’t an issue since most people refuse to do the recommended OEM drain intervals anyway. Everyone in America is “unique” and will automatically rationalize that they’re “special” and will throw the OEM drain interval out the window for doing it their way.

So, they’re wasting money too. They’re just thinking that they’re saving money in their form of wasteful behavior.