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Big Mac · Sep 4, 2007, 06:45 PM

Any views on whether/when to switch to synthetic motor oil?

chabig · Sep 4, 2007, 07:00 PM

I did it because I thought it would be better for my engines. I think you can do it anytime.

stevesnj · Sep 4, 2007, 07:19 PM

Originally Posted by Big Mac

Any views on whether/when to switch to synthetic motor oil?

Its best if you call the dealership repair desk and ask them for sure. Some vehicle manufactures warranties specify that synthetic oil will void the warranty but most modern engines should be okay. Better to be safe than sorry and ask first. I use Mobile 1 Extended 15k mile oil and during the winter here in the cold Northeast the engine doesn't drag at startup like from the use of non-synthetic.

chabig · Sep 4, 2007, 08:10 PM

It is absolutely illegal for the manufacturer to void the warranty based upon the type of oil you use.

Honda and Acura Articles and Information - Warranty Laws and Synthetic Oil

Chris

hookem2oo7 · Sep 4, 2007, 08:36 PM

If you're switching to synthetic on a freshly built motor (not brand new from the factory, as these have already been broken in, but a rebuilt engine) it's best to wait until the motor has been broken in (3-5k miles, opinions on this vary) because synthetic oil's lubrication is "too good" for the rings to properly seat against the cylinder walls. On a new car, you can switch whenever you like. I know a couple of manufacturers are shipping their vehicles with synthetic oil from day one...

stevesnj · Sep 4, 2007, 08:39 PM

Originally Posted by chabig

It is absolutely illegal for the manufacturer to void the warranty based upon the type of oil you use.

Honda and Acura Articles and Information - Warranty Laws and Synthetic Oil

Chris

Thanks for the correction

Big Mac · Sep 4, 2007, 08:42 PM

Good info, thank you. I was a bit concerned about making the switch because I thought I read that it may be a better idea to stay with traditional in a car that has been using it.

hookem2oo7 · Sep 4, 2007, 08:46 PM

you may have read that somewhere...

On an older car with lots of miles, synthetic oil can actually be detrimental to its health. The detergent properties are superior to those of dino oil, so caked on carbon deposits that could very well be holding the engine together (especially the rings), so to speak, could be washed away resulting in loss of compression, etc.

Big Mac · Sep 4, 2007, 09:01 PM

How would you define "lots of miles"?

Laminar · Sep 5, 2007, 12:15 AM

Depends on the vehicle. 200-300K+ probably.

Madison · Sep 5, 2007, 04:16 AM

I've been servicing and repairing industrial equipment for 18 years, including changing oil. I've worked with petroleum, synthetic/petroleum blends, and straight synthetics. There is NO doubt in my mind, none, that synthetic oil is VASTLY superior to petroleum oil in every way, shape, and form. As a matter of fact, not one single piece of equipment that my company distributes is even offered with petroleum anymore, it's all blends and straight synthetics.

Yes, it costs more, initially, however, you'll save a ton in the long run. I've been running synthetic in my service truck for those 18 years, have driven over 850,000+ miles in the process, never had so much as a hiccup with my trucks, Fords, Dodges, GMCs, diesels, and gas engines. Go synthetic and don't look back.

Tom

Kevin · Sep 5, 2007, 05:09 AM

mobile 1 synthetic all the way.

tkmd · Sep 5, 2007, 11:55 AM

There is nothing "bad" about switching to a synthetic oil. Regular oil (usually the cheapest at a auto store ) has many different length chains of hydrocarbons, however, it has been determined that only hydrocarbons in the oil of a certain length aid in lubricating the engine. Under heat and pressure the "useful" chains get broken down and essentially become useless for lubrication. I forget exactly what length is optimum but synthetic oil has a significantly higher % of this length. Thats why people recommend oil changes every 3-5 K miles on a regular oil but with synthetics is easily double 5-8K miles.

I've heard stories that if you started with regular oil you cant change to synthetic oil - thats BS. Some people go so far to say that older engines built in the 70's and 80's arent machined to modern "tight" tolerances so synthetic oils will leak out. I am confident that this too is BS : my 4 L 6 cylinder Jeep engine is a dinosaur, it was designed in the 70's and has not changed much till Jeep dropped it from its lineup 2007. I have been running mobile one synthetic in it since day one. No leaks - no problems.

So to answer your question yes change it to synthetic and stop worrying.

Person Man · Sep 5, 2007, 12:25 PM

I use AMSoil in my car.

Cut through the marketing crap and the stuff is pretty good. They claim 25-35K per oil change, but I change the filter (and the oil) every 6 months, which is about 8000 miles, the way I drive.

I have their lifetime air filter in my car, too. Take it out once a year, clean it, and reapply their thick filter oil. Works great.

With my current car, a 2004 Nissan Sentra that I bought brand new, I went 3750 miles on the factory oil, to break it in, and then converted to AMSoil. But, my last two cars were older and I converted them right off the bat. One was a used 1995 Ford Contour with 104,000 miles on it and the other was a used 1989 Pontiac Grand Am with 175,000 miles on it. Neither car had any trouble with it.

My brother is a mechanic and he keeps the cars running in our family. My brother recommends AMSoil first, and Mobil One second. He says both are good. All our cars use AMSoil. When it comes to cars and their maintenance and repair, I trust him absolutely. He has saved my behind on several occasions because I'm an idiot when it comes to this sort of thing (aside from routine stuff like checking oil/fluid levels, etc). I'm not entirely stupid, though, so it really annoys me when he tries to explain something to me using medical analogies ("Basically I took your car's gallbladder out." WTF??).

I think the next time he asks me about some new medicine he's been given (I'm a doctor), I'll tell him something like, "basically it's a speed governor for your heart," or something like that.

Go for the synthetic, dude.

StrongBadinator · Sep 10, 2007, 11:43 AM

Originally Posted by Big Mac

Any views on whether/when to switch to synthetic motor oil?

Yes, synthetic is great. It's only worth it when:

1. You don't burn oil
2. You don't leak oil.

If you have to keep adding oil, it's kind of stupid to get synethetic. Synthetic does not really 'reduce friction' or 'add power', but the oil polymer chains are stronger, so they do not 'wear out' and 'break down' like regular motor oil. This means you can go longer in between changing the oil. If you drive gently, and don't beat on your car, it's not really bad for anything to go about 7-10k between changes. If you drive more aggressively, change it around every 5k.

One thing to note: On higher mileage engines that used REGULAR oil, switching to synthetic can cause oil leaks. The cleaning agents in synthetic oil can remove the crude near worn out seals, which then leak afterwords. It did this on my SVX, and on my neon. For the hondas, it did not start leaking. >shrug<

StrongBadinator · Sep 10, 2007, 11:45 AM

Originally Posted by tkmd

There is nothing "bad" about switching to a synthetic oil. Regular oil (usually the cheapest at a auto store ) has many different length chains of hydrocarbons, however, it has been determined that only hydrocarbons in the oil of a certain length aid in lubricating the engine. Under heat and pressure the "useful" chains get broken down and essentially become useless for lubrication. I forget exactly what length is optimum but synthetic oil has a significantly higher % of this length. Thats why people recommend oil changes every 3-5 K miles on a regular oil but with synthetics is easily double 5-8K miles.

I've heard stories that if you started with regular oil you cant change to synthetic oil - thats BS. Some people go so far to say that older engines built in the 70's and 80's arent machined to modern "tight" tolerances so synthetic oils will leak out. I am confident that this too is BS : my 4 L 6 cylinder Jeep engine is a dinosaur, it was designed in the 70's and has not changed much till Jeep dropped it from its lineup 2007. I have been running mobile one synthetic in it since day one. No leaks - no problems.

So to answer your question yes change it to synthetic and stop worrying.

It's just that with higher milage engines, switching to synthetic may cause leaks to appear.

BadKosh · Sep 10, 2007, 12:23 PM

AmsOil For SURE! I have a 95 Jetta with 200K miles on it. I put AmsOil in at 47K. I change it every 15K miles. I had the top end replaced at 150K due to a valve guide issue and when opened up, the engine looked NEW! Remember to switch your oil filter to an AmsOil one too.