When to switch to Synthetic oil?

The subject is practically a religion. It sure would be nice if someone could post references to serious evidence. (Me, I'm just gonna put in Mobil 1 at the first scheduled oil change, use Toyota filters, and not worry about it.)

 

im with you richard. also just to back it up our prius guru, john, switched at about 1000miles.btw my mercedes warrantyfor engine is voided (yes its true if i dont use mobile1) reason as i interpret it has to do with oil surging or bubles or some such thing iknow you love it when i talk tecno

 

5k miles or 6 months according to Toyota for the Prius.

I don't think I'm going to wait that long, though. Can't really go wrong following John's procedure, as far as I can tell.

 

I would strongly encourage everyone wanting to switch to synthetic oil to wait a minimum of one and generally two oil changes before they switch. The "break in" period, while a mystery in actuality, depends on friction to wear the high spots from components, resulting in smooth, uniform, or a least mated, surfaces. This is critical in the cylinders, but is also important in bearings. Many manufactures still use a break in additive, although some enter the system as a result of "pre-lubes" used during assembly. Many an engine manufacturer in the automotive and marine industry has stressed that best overall performance, life, and economy will result when the initial oil change is done at the scheduled interval. Many also have encouraged waiting one additional interval to allow for better component run-in. When you consider the quality of today's motor oils, there should be no concern about doing this. Thereafter, the use of synthetic oils tends to greatly reduce start-up and cold temperature wear resulting from poor cold oil flow. The Prius engine runs in a manner that tends to reduce stresses, however any engine will benefit over the long term from using synthetic oils. The problem is that with todays engines, there is little data available to support this since conventional oils are so good and modern engines are so forgiving. The laboratory oil tests, conventional vs synthetic, however speak for themselves.

 

Okay, I'll do that, then. :lol:

 

For what it's worth, I read on one of the synthetic motor oil manufacturers' sites that you don't have to wait for a break-in before switching to synthetic. They claim you can use it on a brand-new engine.

However, I have seen no convincing evidence that synthetic actually makes a difference. I'd like to see a proper scientific study showing an improvement in mileage, or longer engine life in this particular engine (which runs so much less, and uses its own unique low-stress starting routine).

 

True (see the Mobil 1 website for references), and "I agree". I will use Mobil 1 not because I expect any significant increase in performance, economy, or engine life, but because I want to use as little petroleum as possible. Which is pretty much why I bought a Prius in the first place.

 

So what's Mobil 1 actually made of? And how much petroleum goes into the manufacture of it? (It must take energy to manufacture.) And at one oil change every 5,000 miles, are you really using less petroleum?

 

I posed the break in question to toyota. they stated that there was no reason to wait to fill with synthetic.

 

I posted the synthetic question to Toyota as well. The response was to wait until the first oil change, and that once I go synthetic I could never go back. Although I don't believe the latter.

 

Now that you mention it, I think it was on the Toyota site that I read that: synthetic once, synthetic forever. Note that whether or not there are technical reasons for it, you could void your warranty by disregarding their injunction. But I do believe them. I have heard this before, and I see no reason for Toyota to lie about it.

And I'd still like to know what Mobil 1 is actually made of. And if the answer is "polyoleophenylestereloloeopropolyglycolomolicolacetate," then I want to know what that is made of! And how much petroleum goes into the manufacturing process. (Although if you burn 100 gallons of gas between oil changes, even plain old dino oil is adding a pretty small amount of petroleum to your consumption.)

 

I am pretty sure that using sythtetic oil in the Prius 76 hp, 5000 rpm, low-stress starting, frequently off engine, offers no advantage.

 

I am going to switch to synthetic at the 5,000 mile service mark.

 

That site does not actually say that you can switch back to dino. They just say synthetic won't void your warranty. Toyota says it's fine to use synthetic, but that if you use it once, you must use it forever. So switching back to dino after using synthetic violates Toyota's express recommendation. And that might void your warranty.

 

FYI -

I spoke with my Brother, Toyota Mechanic, about this very item. He said there was no problem switching back and forth. He has been with Toyota for over 15 years now. His main concern, in regards to oil, is keeping the oil/synthic clean. Change it reguarly. He also made the comment about using a GOOD oil filter and AIR filter. This is how contaminants "get in" He recommends sticking with Toyota brand filters. He has always taken car of my cars, and I have never had any problems.

 

If it ain't broken, don't fix it. Does the Echo need synthetic oil? The Prius needs it even less.