New Prius Owners - Don't use Synthetic Oil in the beginning

prolene refers to his Honda S2000 engine. That engine is unique--look at the specs, i.e., 2hp/ci

 

DINO oil has stood the "test of time" and is both dependable and efficient. To say an engine won't last as long using DINO is hype, that has never been proven by evidence, in fact there are MANY well maintained, high mileage engines around that have never seen synthetic oil.

That said, synthetic has some unique properties that can give specific performance or other special benefits, like other modificiations do. BUT to imply that synthietic is necessary to get a full lifetime out of an engine is bunk.

On my next oil change, I'm planning on putting in synthetic, mostly to see if I get better mileage, but also it's suggested syn oil might be more enviro friendly (haven't seen this proven, but certainly isn't worse). When my Prius finally fails someday, I highly doubt it will have anything to do with an oil related problem.

 

I agree, with some exceptions.

If the owner tends to be lazy about oil changes anyway, at least the synthetic will hold up better. Most dino oil will fall apart quickly once the additive package is used up.

In severe oil use, say a turbocharger or a hydraulic unit injector, a regular oil may coke or foam. Or if the motor is prone to sludging. A synthetic oil is much more resistant to such problems.

Severe cold, especially -25 F or colder, isn't even up for debate. Most dino 5W-30 will turn solid as a brick at -29 F. A synthetic 5W-30 should be good to at least -45 F, a good 0W-30 or 0W-20 to -70 F.

Since we're stuck with 6 month or 5,000 mile oil changes anyway, I would suggest the vast majority of Prius owners will do well with a regular 5W-30

I still think the fuel economy benefit of "thinner" synthetic oils is a bit overblown. The ACEA has performed extensive testing of motor oils to determine fuel economy "improvements" and, for the most part, they found minimal improvement that wouldn't be noticed.

The "reference oil" is a sturdy HD 15W-40, which is actually recommended by car makers in Europe, especially BMW and Porsche. A 5W-30 on average improved the fuel economy by 1.0%. A 5W-20 improved the fuel economy by 2.5%.

I've noted the same thing when I ran viscosity grades from 0W-30 to 15W-50, including a HD 15W-40 and a HD 5W-40, in my 1990 4Runner: there was no noticeable fuel economy difference. Same as my 1992 Honda Prelude SR.

I was a lot more concerned about cold temperature pumping, so that's why I ran synthetic 0W-30 in winter. I also feel that under our North American driving conditions, a "thinner" oil will protect just as well as a "thicker" oil. In stop-n-go and especially short trip operation, the thinner oil has many advantages.

But to hear of folks who gained 10-15% fuel economy just by switching brands of motor oil is highly doubtful.

 

Re: New Prius Owners - Don't use Synthetic Oil in the beginn

I started using synthetic oil after my Toyota Tercel engine only got 140 k miles even though I change the oil every 3750 miles as recommended by Toyota. The car never lost a dorp of oil, it all burned in the engine. I did have a sludge flush around 70K because it was recommended by my dealer mechanic.

I think synthetics should bo okay in a new engine because Toyota is manufacturing engines, not making a one off like a race car mechanic. I am going to switch, at 5000 miles, to synthetics because they seem to flow better at lower temps. Maybe I am wasting my money but at least I'll have peace of mind.

I don't know if the ICE has an electric oil pump, that would lubricate the engine before it started, but that would be the only reason I would even consider running regular oil.

 

Re: New Prius Owners - Don't use Synthetic Oil in the beginn

I have seen both synth and dino under an electron microscope. The synth looked uniform in particle size. The dino oil looked like a jumble of particles of differnt sizes and shapes.

Synthetic oil is perfect for sealed and unsealed environments it holds contaminates better than dino oil due to uniform particle size.

I personaly have run both in turbo and non turbo engines. After opening up the engine that used synthetic and one that did not I will always use synthetic. These were farm pickups with over 100k plus miles and were worked to death. It was always the other parts that failed not the engine.

If you drove in a perfect world dino oil would be fine.

As for break in - It is a thing of the past. Computer controlled manufacturing makes tolarances perfect in the engine. Most engines are broken in by 400 miles and continue to improve up to a point then degrade over time.

The corvett engine is run for 20 minutes on the testing block. Then filled with Mobile 1.
I beleive the Toyota engine is built with as much care as the vette's. 1.5 Liters pounding way is as much stress or more than the vettte.

Blue

 

Re: New Prius Owners - Don't use Synthetic Oil in the beginn

I think there are still many legitimate questions on how oils work, especially their ability to control acid buildup, sludge buildup, to disperse particles, etc.

For some reason, I receive complimentary subscriptions to Practicing Oil Analysis and Machinery Lubrication. There are some interesting articles that pertain to our questions, I hope they help you:

http://www.noria.com/learning_center/categ...p?articleid=477

http://www.practicingoilanalysis.com/artic...oup=OilAnalysis

http://www.practicingoilanalysis.com/artic...oup=OilAnalysis

http://www.practicingoilanalysis.com/artic...oup=OilAnalysis

http://www.practicingoilanalysis.com/artic...oup=OilAnalysis

http://www.practicingoilanalysis.com/artic...p=Which%20group?

http://www.machinerylubrication.com/articl...up=Lubrication2

http://www.machinerylubrication.com/articl...oup=Lubrication

http://www.machinerylubrication.com/articl...up=Lubrication2

Hope this helps.