oil

[OxyG3nE]

what is the best synthetic oil to use in a yaris and also the best filter?

[joey1320]

man you will get a lot of answers to this question... i'll go for the OEM filter and Castrol Syntec oil. Just my 2cents. I bet others will disagree.

[Kaotic Lazagna]

try searching this topic. there's a crap load out there. a lot say Wix filters and Napa oil, but you want synthetic, so Mobil 1, Royal Purple, and Amsoil is what members here recommend (if i remember correctly).

[static808]

what is the best synthetic oil to use in a yaris and also the best filter?

in any automotive forum, them be "fightin' words." people get really heated over this one, and debates become endless. but the one consensus i can think of from all the stuff i've read?? change your oil on regular intervals, meaning, be very consistent with your oil changes, and you'll be fine with pretty much any oil, EVEN dino oil (this one must be changed more frequently). is synth better?? OF COURSE! will your engine die on you if you change your oil with quaker state dino every 3000 miles?? probably not...

--B

ps: i use amsoil ASL 5w-30 and either amsoil or wix filter...

[Vervepipes]

My synthetic of choice is Amsoil... it helps that I'm a preferred customer with option to become a resaler :P

[joey1320]

in any automotive forum, them be "fightin' words." people get really heated over this one, and debates become endless. but the one consensus i can think of from all the stuff i've read?? change your oil on regular intervals, meaning, be very consistent with your oil changes, and you'll be fine with pretty much any oil, EVEN dino oil (this one must be changed more frequently). is synth better?? OF COURSE! will your engine die on you if you change your oil with quaker state dino every 3000 miles?? probably not...

--B

ps: i use amsoil ASL 5w-30 and either amsoil or wix filter...


good post. follow his advice! change the oil regularly. i'm gonna get me a "hourly meter" to keep track of how many hours my engine is runing and do my changes based on that. i have yet to decide what brandname to go with so once i do i'll post info.

if you dont want to get all fancy like me just change it every 3k if you drive your car normally. if you decide to go auto x'n or do something like that change it after you are done.

[PetersRedYaris]

I don’t get why people change their oil more often than recommended. :confused: 3000 mile intervals is excessively wasteful. If you drive normal, do like the manual says and change it every 5000 miles. You listen to your owner’s manual for bolt torque specifications, fuel octane rating recommendations, and fluid type/weight specifications, and you wouldn’t stray from those. But when it comes to oil changes, everybody insists Toyota’s recommendation is too long. Why buy an eco-friendly economy car and then waste all that extra oil? 5000 on regular oil and 7500 on synthetic is fine. :laugh:You won’t extend the life of your Yaris with smaller intervals.:laugh:

[static808]

I don’t get why people change their oil more often than recommended. :confused: 3000 mile intervals is excessively wasteful. If you drive normal, do like the manual says and change it every 5000 miles. You listen to your owner’s manual for bolt torque specifications, fuel octane rating recommendations, and fluid type/weight specifications, and you wouldn’t stray from those. But when it comes to oil changes, everybody insists Toyota’s recommendation is too long. Why buy an eco-friendly economy car and then waste all that extra oil? 5000 on regular oil and 7500 on synthetic is fine. :laugh:You won’t extend the life of your Yaris with smaller intervals.:laugh:

completely agree. i'm still used to the antiquated system of every 3000 miles! if the manual says 5000, then do it. with our amsoil, we change every 7500 or 6 months, whichever comes first. JUST BE DILIGENT...and your engine will be fine, no matter the oil...

--B

[Kaotic Lazagna]

i think it's because of driver/owner comfortability and media propaganda that we change our oil every 3,000 miles, and possibly driving conditions.

[Pavel Olavich]

Here's my take on this oil thing. If your engine is brand new, don't replace the factory oil until after the engine is broken in and even then, wait till past 3,000 miles, to make sure the parts are warn optimally.

Stay away from mineral oil. It's not bad but there are better choices to provide more longevity to your engine.

Don't get sucked into the industry wide Bull Shit thinking that one must replace the oil every 3,000 miles. This is robbery by the industry against all of us.

Don't judge the worth of your oil based on just looking at it. Just because it is a bit dark does not necessarily mean it is too dirty to provide protection.

Use Mobil1 Synthetic EXTENDED LIFE, which they claim is good for 15,000 miles. But I would suggest not going past 10,000 miles just to be safe. Using this oil will save you money by making changes less frequently, and it provides better engine protection then mineral, and does so longer in time.

Stay away from dillusions, and superstitions that you'll read all over the internet. The best independently proven oil protection is Amsoil synthetic, but as a compromise to cost, I use Mobile1 Extended synthetic which is nearly as good.

Don't waste your money on too frequent changes. It is a dillusion that you're adding more protection to your engine, and it just wastes money needlessly.

I prefer Mobile1 filters. Are they better? I don't know I have no proof, however since I use Mobile1 Syn Extended life, I naturally go with their filters.

Learn to change the oil yourself, as it is very fast and easy, and you know damned well that it is the premium stuff being put into your car and not the car of the mechanic.

Save your money by changing only every 10,000 miles, go with a good synthetic, especially a product with extended life, use a good filter, and all this will conspire to give you better engine protection, better MPG, and save you $$ by not requiring too frequent changes.

My 2 cents....

[Vervepipes]

My dealer actually sets the oil change intervals at 8000Km's, I dont know if it's Toyota nation wide though

[earljail]

My dealer actually sets the oil change intervals at 8000Km's, I dont know if it's Toyota nation wide though

I'm pretty sure that's for all of Canada. I'd guess that the U.S. interval is 5000 miles.

For the OP, I switched to Mobil 1 at the first scheduled oil change, and use OEM filters. I bring my own oil to the dealer, and they use my oil and their filter. As soon as warrantee is done, I'll buy a box of Toyota OEM filters and do it all myself.

[hystria]

Probably Motul - but is hard to find here in Canada
Otherwise Canadian Tire sells Red Line, another good choice
I personally don't trust that much Amsoil. They publicize a lot on internet, "best synthetic oil" on Google returns dozens of sites all on Amsoil :confused: . Any of those sites are that kind of stuff saying Amsoil is the best... ok... :rolleyes:

Mobil 1, Mobil 1 Extended Performance and Castrol Syntec are only intended to give better start-up on cold days, not for extended oil change intervals

[OxyG3nE]

thanks everyone for the info.. :)

[Pavel Olavich]

Probably Motul - but is hard to find here in Canada
Otherwise Canadian Tire sells Red Line, another good choice
I personally don't trust that much Amsoil. They publicize a lot on internet, "best synthetic oil" on Google returns dozens of sites all on Amsoil :confused: . Any of those sites are that kind of stuff saying Amsoil is the best... ok... :rolleyes:

Mobil 1, Mobil 1 Extended Performance and Castrol Syntec are only intended to give better start-up on cold days, not for extended oil change intervals

You're wrong...it says right on the label "15,000 Miles".

[hystria]

You're wrong...it says right on the label "15,000 Miles".

I know I'm wrong :wink: that's what I'm using right now, the Mobil 1 Extended Performance + K&N filter, it has 2000 miles and the oil got quite dark, now tell me If a real synthetic would do so, anyway, it's the last time I'm using a pseudo synthetic. if one needs to spend more money at least buy real synthetics, i.e. Motul, Red Line or Amsoil

[spkrman]

I know I'm wrong :wink: that's what I'm using right now, the Mobil 1 Extended Performance + K&N filter, it has 2000 miles and the oil got quite dark, now tell me If a real synthetic would do so, anyway, it's the last time I'm using a pseudo synthetic. if one needs to spend more money at least buy real synthetics, i.e. Motul, Red Line or Amsoil

very many tests wouldn't agree :)

[91drggndime]

I use WIX filters and Castrol Oil.. but since I do not have a parts store that sells WIX filters.. With this oil change, I went with Castrol oil and Purolator oil filter.

[Black Yaris]

I know I'm wrong :wink: that's what I'm using right now, the Mobil 1 Extended Performance + K&N filter, it has 2000 miles and the oil got quite dark, now tell me If a real synthetic would do so, anyway, it's the last time I'm using a pseudo synthetic. if one needs to spend more money at least buy real synthetics, i.e. Motul, Red Line or Amsoil

well I change my oil every 5000 miles I have used mobile one 5-30 full synth and amsoil 5-20 full synth and now currently running 0-20 mobile one full syth, and after every oil change oil has still look a good golden color, I have always used Champ brand filters except this last time I gave fram a try

[Pavel Olavich]

I know I'm wrong :wink: that's what I'm using right now, the Mobil 1 Extended Performance + K&N filter, it has 2000 miles and the oil got quite dark, now tell me If a real synthetic would do so, anyway, it's the last time I'm using a pseudo synthetic. if one needs to spend more money at least buy real synthetics, i.e. Motul, Red Line or Amsoil

So it got dark....now you're a chemist :smile:

So what...it got dark...this does not mean it is not working as expected.

Relax and stay with it through 10,000 miles....you'll be ok and so will your engine.

Why do you call it "pseudo"? It's the real deal, and like mineral oil, it too will change color with use...this is okay!!

[Pavel Olavich]

well I change my oil every 5000 miles I have used mobile one 5-30 full synth and amsoil 5-20 full synth and now currently running 0-20 mobile one full syth, and after every oil change oil has still look a good golden color, I have always used Champ brand filters except this last time I gave fram a try

Going against the Toyota manual means your 0-20 oil could screw up your engine...why are you doing this?????

And chaning the Synthetic oil every 5,000 miles seems very foolish, and wasteful of your $$, and misses the entire point of using synthetic.

Don't buy this dillusion of thinking that just because the oil color changes, that it needs to be replace...this is based on dillusion void of facts, friend.

Save your $$....do it every 7,500 or 10,000 miles, and use the correct viscosity as dictated by the owners manual.

[Black Yaris]

Going against the Toyota manual means your 0-20 oil could screw up your engine...why are you doing this?????

And chaning the Synthetic oil every 5,000 miles seems very foolish, and wasteful of your $$, and misses the entire point of using synthetic.

Don't buy this dillusion of thinking that just because the oil color changes, that it needs to be replace...this is based on dillusion void of facts, friend.

Save your $$....do it every 7,500 or 10,000 miles, and use the correct viscosity as dictated by the owners manual.

Hey guy there is a Toyota TSB to increase gas mileage for the 1NZ motor use 5-20 or 0-20 synthetic oil
and god forbid somthing were to happen to this engine I do need a proof the oil was changed every 5000 miles synthectic or not, so untill the warranty is up 5000 miles it is, after that I will go more than that...

[hystria]

well I change my oil every 5000 miles I have used mobile one 5-30 full synth and amsoil 5-20 full synth and now currently running 0-20 mobile one full syth, and after every oil change oil has still look a good golden color, I have always used Champ brand filters except this last time I gave fram a try

that's interesting to know, do you run on 89 or higher gasoline ?

[Pavel Olavich]

that's interesting to know, do you run on 89 or higher gasoline ?

Running octane higher then 87 is just wasting money, and doing this actually makes the car run UNDER powered, as the combustion is RETARDED...for most power, use octane 87, as the Toyota manual dictates....save your money....more octane means LESS POWER...especially for very small engines having low compression....

[nsmitchell]

I only use REAL OIL! None of that "synthetic voodoo snake oil". :wink:

[Spades]

meh, I am a broke little bastige, so I use Valvoline Synthetic Blend 5w30, and STP filters.

Royal Purple,Mobile 1,Amsoil, and others are much better, but they also cost double or more per quart than the valvoline does.

After some research, I had decided on the last 3 cars I have owned to use semi-synthetic, as there are pro's and cons to using full sythetic or just regular oil. So, after much debating I settled on a blend.

EDIT: on the thread jacking question of octane, all octane rating really does is determine at what point predetionation occurs. If you are running a engine with high compression or forced induction high octane fuel is a good idea, but on a gas miser car that was designed to run on pisswater gas, you won't notice any performance differance.

[Galavoxx]

I agree with Pavel that running higher octane will waste money but no need to get worked up. I have to say though, the Yaris has pretty decent compression for an econocar. If the damn thing would only rev higher!!

I use Redline Full Syn 5-30 with a Mobil 1 or K&N high flow filter. These two filters are made by the same manufacturer and are good quality. And Redline is just the biz.

[Spades]

Yeah, mobil 1 filters rock(can't afford them since I change my oil every 1,500-2,500 miles).

[/Threadjack]

As far as rev'ing higher...how high do you need? I mean, jeebus, I power shift at 6300RPM's to get a nice 1 to 2 chirp...seriously...why would you want it to have a higher redline? 6k+ for hp range is plenty high enough...

The cars top speed is governed, so it wouldn't go any faster. I could care less if the car made its peak power and you shifted at 3k RPM's as long as I had enough gearing to go 100mph(for the occasional 1/4 mile run,if the car was actually faster),lol.

Now, more low end torque, that is what the car really needs!

[/Threadjack]

[Galavoxx]

Yeah, mobil 1 filters rock(can't afford them since I change my oil every 1,500-2,500 miles).

[/Threadjack]

As far as rev'ing higher...how high do you need? I mean, jeebus, I power shift at 6300RPM's to get a nice 1 to 2 chirp...seriously...why would you want it to have a higher redline? 6k+ for hp range is plenty high enough...

The cars top speed is governed, so it wouldn't go any faster. I could care less if the car made its peak power and you shifted at 3k RPM's as long as I had enough gearing to go 100mph(for the occasional 1/4 mile run,if the car was actually faster),lol.

Now, more low end torque, that is what the car really needs!

[/Threadjack]

More low-end would be good too, of course. As far as redline goes, higher revs usually equal higher hp numbers on top. I'm just dreaming of one more thing that would make a nice hi-po Yaris motor: turrrbo, pretttty forrrged things, lightened things, head-job, fuel management... etc., etc. Higher revs are always fun but not always practical. :burnrubber:

[Spades]

[/threadjack]

Higher RPM's do not more HP numbers make...just because riceboy in his built b18 integra makes his peak HP at 9k RPM's does not mean a yaris will.

In the performance section a turbo kit for the yaris is being tested as we speak...and if I remember correctly they are around 180hp without building the bottom end to make the engine rev higher. High RPM's mean more to go wrong...rods through the block are a example that comes to mind.

It will be very hard to use a stand alone engine management system to control the motor at high RPM's, because the yaris' throttlebody is electronic...much more difficult to get a EMU that will work with it.

Fuel modifications, bigger valves & cams, and boost however, these are things we both agree on!

[/threadjack]


Anyone wish to start the time honored debate of Synthetic VS Synthetic Blend?

[Black Yaris]

that's interesting to know, do you run on 89 or higher gasoline ?

yes I run shell 89 oct at min

[Galavoxx]

[/threadjack]

Higher RPM's do not more HP numbers make...just because riceboy in his built b18 integra makes his peak HP at 9k RPM's does not mean a yaris will.

In the performance section a turbo kit for the yaris is being tested as we speak...and if I remember correctly they are around 180hp without building the bottom end to make the engine rev higher. High RPM's mean more to go wrong...rods through the block are a example that comes to mind.

It will be very hard to use a stand alone engine management system to control the motor at high RPM's, because the yaris' throttlebody is electronic...much more difficult to get a EMU that will work with it.

Fuel modifications, bigger valves & cams, and boost however, these are things we both agree on!

[/threadjack]


Anyone wish to start the time honored debate of Synthetic VS Synthetic Blend?

I'll avoid the oil debate but still disagree on the RPMs. :biggrin: 9000rpms is nothing for a 1.5L engine, if built properly. A 1.5L should be able to do 12k with no issues. But why spend the money. Engine management is a huge issue, of course. 180hp on a stock bottom with a 6500 rpm redline does make all the fuss of getting into anything else seem almost pointless.

and for that matter....... Synthetic oil rocks!!! :headbang:

I couldn't help myself. :rolleyes:

[Spades]

yes I run shell 89 oct at min

[/threadjack] (again)

High octane rating only determines at what point the fuel will combust. A high octane fuel is to prevent a thing called "Predetonation" from occurring.
Predetonation is not a term you ussually hear in parking lots full of kids showing off their cars, ussually it is used at the dragstrip listening to guys talk about their 400+HP 4cyl boosted cars.

Predetonation is what happens when due to pressure in the combustion chamber the fuel ignites prematurely before the spark plug triggers. This is a very bad thing, because if the number 1 cyl predetonates, it goes against the crankshaft being turned by the pistons that are firing in the correct order with their spark plugs.

The force inside a cylinder chamber becomes increasingly higher when you try to force 20 PSI of boost into it. When the piston goes on what is called the compression stroke(the stroke where it mashes the mixture of air and gasoline together in preporation to be ignited) the pressure can sometimes be enough to cause the mixture to explode.

High octane rated fuel is used to prevent the gasoline and air mixture from blowing up before it is supposed to. The only benifit to using high octane fuel on a car that was designed for 87 octane piss water is that it sometimes burns cleaner because some gas stations may put more adatives in it and sometimes it is a slightly better grade of fuel.

If you ever get boosted or change the compression to something radical(say 14 to 1) then look into 89 octane, untill then, feel free to waste your cash on the gas that costs 30 cents more a gallon.

[BailOut]

...it says right on the label "15,000 Miles".
It sure does, and K&N says their oil filter can go with that, so that's exactly what I'm doing for both our vehicles.

I plan to change the oil right around the time we re-register the cars annually.

[Black Yaris]

[/threadjack] (again)

High octane rating only determines at what point the fuel will combust. A high octane fuel is to prevent a thing called "Predetonation" from occurring.
Predetonation is not a term you ussually hear in parking lots full of kids showing off their cars, ussually it is used at the dragstrip listening to guys talk about their 400+HP 4cyl boosted cars.

Predetonation is what happens when due to pressure in the combustion chamber the fuel ignites prematurely before the spark plug triggers. This is a very bad thing, because if the number 1 cyl predetonates, it goes against the crankshaft being turned by the pistons that are firing in the correct order with their spark plugs.

The force inside a cylinder chamber becomes increasingly higher when you try to force 20 PSI of boost into it. When the piston goes on what is called the compression stroke(the stroke where it mashes the mixture of air and gasoline together in preporation to be ignited) the pressure can sometimes be enough to cause the mixture to explode.

High octane rated fuel is used to prevent the gasoline and air mixture from blowing up before it is supposed to. The only benifit to using high octane fuel on a car that was designed for 87 octane piss water is that it sometimes burns cleaner because some gas stations may put more adatives in it and sometimes it is a slightly better grade of fuel.

If you ever get boosted or change the compression to something radical(say 14 to 1) then look into 89 octane, untill then, feel free to waste your cash on the gas that costs 30 cents more a gallon.

we had this debate a long time ago... just do a thread search to see what realy happens... our car CAN tell the difference between octanes and does get better gas miles with higher octane

[Galavoxx]

we had this debate a long time ago... just do a thread search to see what realy happens... our car CAN tell the difference between octanes and does get better gas miles with higher octane

...even if it runs better and gets better mileage, use of a higher octane that your car does not need can lead to carbon build up in the combustion chamber. This is especially true over the life of the engine. What may run good now, may have some issues after 100k miles. You want to make sure the fuel in the combustion chamber burns off quickly and completely. Without the added compression to assist in the process, 87 octane burns hotter and faster than 91. So your car may run better on 91 and get better gas miles now but this doesn't mean it will be better over the life of the engine. Just my 2 cents.

[Pavel Olavich]

It has been proven for years, all over the web, that small 4 banger car and motorcycle engines actually produce LESS POWER with higher octane gas. It is a myth to think that our Yaris engines benefit from higher octane gas, no such thing as "imrpoved MPG" either. Our Yaris engines are not even chipped for higher then 87, and are tuned to run optimally at 87. But try telling this to the boy-racers that equate dicking with their engines and changing the oil monthly with masterbation.

Burning gas higher then Octane 87 is just wasting money, and makes your engine produce LESS POWER...hello?!? Octane slows down the combustion of the gas....leave it for bigger higher compression engines that need that retardation, that are tuned by the factory for higher octane gas. Why would you force the combustion to happen too late in the cycle?!? Incomplete combustion means more stress on the motor, less longevity, and provides a false sense of being. Perhaps you know more then Toyota engineers?

Through my kids, I know many Ricer-Boy teenagers that always fill up their Civics, Integras, Corollas etc with Octane 89 or more...what a waste of money! They have this dillusion of "more power"! Dillusions and superstition are hard to overcome, sadly...

[Pavel Olavich]

Hey guy there is a Toyota TSB to increase gas mileage for the 1NZ motor use 5-20 or 0-20 synthetic oil
and god forbid somthing were to happen to this engine I do need a proof the oil was changed every 5000 miles synthectic or not, so untill the warranty is up 5000 miles it is, after that I will go more than that...


Would you please send me/us all a link of that TSB? I would greatly appreciate it. If there exists such a TSB, then I too would be very interested in using a lighter oil for better MPG...

[Spades]

It has been proven for years, all over the web, that small 4 banger car and motorcycle engines actually produce LESS POWER with higher octane gas. It is a myth to think that our Yaris engines benefit from higher octane gas, no such thing as "imrpoved MPG" either. Our Yaris engines are not even chipped for higher then 87, and are tuned to run optimally at 87. But try telling this to the boy-racers that equate dicking with their engines and changing the oil monthly with masterbation.

Burning gas higher then Octane 87 is just wasting money, and makes your engine produce LESS POWER...hello?!? Octane slows down the combustion of the gas....leave it for bigger higher compression engines that need that retardation, that are tuned by the factory for higher octane gas. Why would you force the combustion to happen too late in the cycle?!? Incomplete combustion means more stress on the motor, less longevity, and provides a false sense of being. Perhaps you know more then Toyota engineers?

Through my kids, I know many Ricer-Boy teenagers that always fill up their Civics, Integras, Corollas etc with Octane 89 or more...what a waste of money! They have this dillusion of "more power"! Dillusions and superstition are hard to overcome, sadly...


I tried to explain why there is octane ratings, but, people don't want to listen. As Pavel said, causing the Fuel to burn later that it is supposed to is not such a good idea. When you get boosted, then go for octane, untill then, all it does is mess with a good design. Remember kiddies, just because the guy down the block puts high octane fuel in his stock 89 civic doesn't mean you should too.

P.S. Sport Compact Car had a whole issue devoted to urban myths about ricer "power" legends. High octane was one of them...and no, you do not get more HP out of higher octane fuel...and also, the octane boosters you buy at walmart actually cause more build up of crap in your fuel system, and most of them don't even boost the octane. Please...stop trying to make a stock compact gas miser car into something its not unless you f--k with the compression or add boost to the equation.

[Pavel Olavich]

I tried to explain why there is octane ratings, but, people don't want to listen. As Pavel said, causing the Fuel to burn later that it is supposed to is not such a good idea. When you get boosted, then go for octane, untill then, all it does is mess with a good design. Remember kiddies, just because the guy down the block puts high octane fuel in his stock 89 civic doesn't mean you should too.

P.S. Sport Compact Car had a whole issue devoted to urban myths about ricer "power" legends. High octane was one of them...and no, you do not get more HP out of higher octane fuel...and also, the octane boosters you buy at walmart actually cause more build up of crap in your fuel system, and most of them don't even boost the octane. Please...stop trying to make a stock compact gas miser car into something its not unless you f--k with the compression or add boost to the equation.


So true Spades....and besides, we all know that if one really wants to add pazzazz to a cars performance, just add a thimble fill of diesel to the....:laugh:

[Go4th]

what is the best synthetic oil to use in a yaris and also the best filter?

AMSOil 5w30
2007 TOYOTA YARIS 1.5L 4-cyl Engine Code 1NZ-FE

FILTERS
Oil Filter........EAO09 AMSOIL Ea Oil Filter (http://www.amsoil.com/storefront/detail.aspx?ID=6900)Oil Filter........51394 WIX 51394 Oil Filter (http://www.amsoil.com/storefront/detail.aspx?ID=9334)Air Filter........49104

:thumbsup:

[YarisTom73]

[/threadjack] (again)
If you ever get boosted or change the compression to something radical(say 14 to 1) then look into 89 octane, untill then, feel free to waste your cash on the gas that costs 30 cents more a gallon.
30 cents more a gallon?? I have given this thought: it's 10 cents a gallon more for "plus", and so, ten gallons equals ONE dollar. The Yaris sedan holds 11 gallons. So, a dollar a full tank? Worth it, for the added cleaning agents' power. Can you say preventive maintenance??

[nsmitchell]

High octane fuel in a Yaris engine makes it retarded! :biggrin:

There! It needed to be said!

[steved]

Here is an interesting article I found that might interest people on this gas dispute.

http://oldeloohuis.com/octane.html

[churp]

Here is an interesting article I found that might interest people on this gas dispute.

http://oldeloohuis.com/octane.html

Boy that guy likes to write!!!! The last 2 paragrahs sum it up though.

THE LAST 2 PARAGRAHS ARE:
"On modern engines with sophisticated engine management systems, the engine can operate efficiently on fuels of a wider range of octane ratings, but there remains an optimum octane for the engine under specific driving conditions."

"If you are already using a fuel with an octane rating slightly below the optimum, then using a higher octane fuel will cause the engine management system to move to the optimum settings, possibly resulting in both increased power and improved fuel economy."


I'm about the oldest codger on this site, and these 2 paragraphs say it all. On pre-engine management engines 8 or 9 pounds of compression ratio would run efficiently on regular (87 octane), any more compression and you would have serious knocking if going up hill or accelerating faster than a snail. (unless you retarded the timing to the point the engine would barely run) 87 octane is not the optimum for 10.5 to 1 compression ratio without engine management. It does fine with regular when driven like the hypers do (little or no load), but under acceleration or going up hill, timing retards (out of the optimum setting) to prevent knock. From his last 2 paragraphs, he basically agrees that premium would help performance and milage during load conditions. Soooo---Hypers don't need it....normal drivers may benefit, depending on the environment and how heavy their foot is!

[Disturb3dMind3d]

http://www.yarisworld.com/forums/showthread.php?t=5744&highlight=tsb+oil

tsb report of 5w-20 oil

[mandriu]

I don't know much, but i do know that the first number in 5w-20 indicates that the in the winter(around freezing) the cold oil would have a lower pour rate than the 0w-20. thereby decreasing lubrication until the engine has reached a warmer temp. In these summer months the 20 of either of the oils would take precedence. Unless you live on the north pole. The actual synthetic oils do not have a state changing property(in normal temps 0C-100C) like mineral oils.

[YarisTom73]

Check this out: http://www.autocarepronews.com/default.aspx?type=art&id=79089&
Apparently Pennzoil has found a full synthetic which changes. I use it in my old Probe without any issues..

[nsmitchell]

Pennzoil, Quaker State, Valvoline... They all send shivers up my spine! Synthetic or not, these companies are scary. I just don't trust them, kinda like Chrysler, Ford and GM! :laugh: