I'd say that site is a result of no time on someones hands. But it does have lots of good information, so his time was well spent i suppose.

Cya

 

That site is hard core. It has all the information anyone could ever need but it is hard to get the information in a concise manner.

 

From experience:
1) No real noticeable difference in MPG or performance using 100%synthetic.
2) Changing back to regular oil or blend after using 100% synthetic caused no problem in my case.
3) Synthetic oil does help reduce engine wear and smoother operation.

For years i had to park outside. In cold weather I would get some valve clicking in the morning after start up. I started using 1 quart of synthetic with each oil change. All clicking stopped immediately. I have tried 100% for about 15k miles and after I just couldn't stand running oil 7,500 miles I went back to my 4 qt +1qt syn blendand changes at 3 to 5k miles. I ran the car another 50k miles and experienced no problems at all.

 

Just because you run with synthetic doesn't mean you have to change it that late. I run 100% synthetic and i still change every 3,000. As i said before, there really is virtually no MPG gains. Performance gains are very rare and limited, however from my experience it does help continue performance for a longer period of time. I.E: helps reduce engine wear therefore helps keep a balance in performance more so than regular oil. I wouldn't suggest mixing synthetic oil with regular oil, but thats your call.

So on so forth.

Cya

 

Synthetic is more stable than regular oil. They can pick and chose which strands to use in synthetic oils. Conventional oils do not have that luxury. Because synthetic oils have more stable strands the oil is less prone to breakdown and thermal viscosity. Synthetic oil doesn't get sticky/gummy as fast as conventional oils which means that you will not be losing horsepower down the road because your now 140,000 motor is full of old viscous oil slowing everything down and heating everything up.

 

Well said.

Cya

 

Synthetic blend, by law, can contain as little as 1% synthetic stock. Using 4 quarts conventional and 1 quart blend gives you a VERY small amount of synthetic. So it's hardly worth the effort.

As for the original topic... I did notice an improvement in mileage in my 97 cavalier Z24, even between brands.

Using dino oil 5w/30 3k change interval, I would average about 26.5mpg. With Mobil 1 0w/30, 5k interval, I would average 29.5mpg. Using AMSOIL 0w/30 w/ AMSOIL filter, 15k interval, I average 32mpg.

Theoretically, increases in HP and mpg are possible with synthetic oil due to reduce friction, reduced heat and reduced engine wear.

 

I track mpg with every mod or change I do... I have found that Amsoil or Royal Purple, Red Line all in 0W30 ....Mobil 1 and German Castrol just a bit behind

 

That's why you change the oil every 3,000 miles. Even if you change conventional oil 3x as often as synthetic oil it will still cost less.

 

i really respect the desire to keep a vehicle in top shape........i feel the same way. however, after reading all these posts, i've got to reply again. i honestly feel that using synthetic oil in the tc is a big waste of money. i could be better used for other things. my friend has a 99 camry with over 200k on it.....all with regular oil. my father has a 90 model toyota truck with almost 300k on it.......all with regular oil.......no leaks.......absolutely no problems. some of you will probably say that the tc is different, but the truth is that it isn't. VERY IMPORTANT POINT HERE............unless you change the INTERNALS of the motor, syn oil is pointless. again, of course it is your choice and maybe the syn gives a little more peace of mind.......and that's worth more than a few bucks.

 

I do recall stating that using synthetic on a stock scion (2az, 1nz) would be pointless...

Cya

 

that's true. it would be. but what i'm saying is that i/h/e modifications are not going to require switching to synthetic oil. all these mods will do is maybe change the pattern of your powerband......they will not bring a need to switch to high priced oil.

 

You are correct, but once i reach the i/h/e point and on, i like to go ahead and switch. But you are right, i/h/e alone wouldn't require a switch. Yes, it does change the pattern of the powerband mostly depending on 4-2-1 or 4-1 header. Intake alone does nothing to the powerband, and exhaust alone rarely does unless its a full system.

Cya

 

well said

 

I did not make myself very clear. Not 4 + 1 blend, but my blend of 4 regular and 1 full synthetic. As for the reccomendation of not mixing, well over 15 years of mixing has not led to any problems. Two cars ran over 200K miles on this blend.

 

just to let you all know there is in-fact a sticky on this right here-->https://www.scionlife.com/forums/vie...=synthetic+oil

regargless of what you drive, synthetic is, hands down, and in every sense, better.

if you change it at 3000 miles you might as well use conventional as the true benefit of synthetic oil is wasted with the frequent changes that conventional oil requires. sorry killerxromances but you are just wasting time/money/perfectly good oil.

With mobil now selling 15000 mile mobil 1 oil and excellent oil filters to go with said oil you can wait until 15000 miles(!) before you change it. If you do follow this route then synthetic oil (to its credit) also becomes cheaper than conventional as it lasts five times longer.

I like to change my own oil, but i don't like to change it that much, I do it more because I know it will be done right, but with synthetic I get that benefit and I dont need to do so as often.

 

Sorry, but to say you waste money using synth on a "non-performance" motor is bunk.
You just have to look at the research and WHAT the oil does to believe that.
Less wear/friction, better cling to hard parts, no gumming all add up to a better solution for your internal combustion engine.
Research has proven this over and over.
Just because most perf cars use this, it doesn't mean lesser cars don't benefit.
The "assumption" is buyers of cheaper cars won't spend the money on synth - and that's a reasonable thing to assume.

Use synth in every engine, and it will run better and last longer, all things being equal.

Scott

 

I would never suggest Synthetic oils in a new engine until breakin period is met. Synthetic will make definate improvements in cold weather starts because it stays fluid to a much lower temp than conventional oil. Engine startup time is probably the demanding test of your oil. On these small engines MPG may not be noticeable, but there is major protection advantages on internal parts witn synthetic vs conventional oil. Additives in synthetics carry deposits away from pressure and stress point to be trapped in the filter to eliminate build up in the engine. Whether using conventional or synthetic, the filter should be changed at 6 months intervals due to moisture content. The oil may still perform beyond this point. Synthetics will maintain their viscosty well beyond that of cobventional oil. I prefer Amsoil XL series at 7500 mile intervals for convienence, although with other Amsoil oils you can extend drain intervals to 25k or even 35k per year changing filter at 6 months interval. As for synthetic tranny oil it does lower operating temp considerable, prolonging life of transmission. For more information check out http://www.mbracingco.com or http://www.amsoil.comThis is my opion only.