For the 3.5 Litre 2GR-FKS V6 Engine, in Australia you are allowed to run 0W20 or 5W30.
Viscosity: Engine protection Vs. enhanced mileage
- Thread starter Sunshine Guy
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This is fair. I paid no attention to who the OP was. I'm kinda bad about that.
OP, welcome to BITOG where splitting hairs is a competitive sport.
Wo ist der gruene Farbstoff ?
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The cold viscosity of 0w-20 and 5w-20 are actually very very close. Just compare the SDS’s.
The statement “If 5w-20 is used, it must be changed to 0w-20 at next oil change” is objectively complete nonsense. It all has to do with CAFE, and Toyota has to recommend 0w-20 at all times for obvious reasons. Only time you might benefit from 0w-20 over 5w-20 is if you happen to live in Antarctica or somewhere that gets extremely cold.
If I were you, I would just use regular 0w-30 or 5w-30 and you’ll actually be able to get more miles/time out of the oil by having some fuel dilution and shearing buffer.
If you’re worried about warranty, do not use Mobil 1 ESPx2 0w20. That oil is green, and it’s super obvious that it’s an oil not recommended by Toyota just by the color of it. If anything happens and you gotta go to the dealership, they will see that green oil, and it will raise questions.
The statement “If 5w-20 is used, it must be changed to 0w-20 at next oil change” is objectively complete nonsense. It all has to do with CAFE, and Toyota has to recommend 0w-20 at all times for obvious reasons. Only time you might benefit from 0w-20 over 5w-20 is if you happen to live in Antarctica or somewhere that gets extremely cold.
If I were you, I would just use regular 0w-30 or 5w-30 and you’ll actually be able to get more miles/time out of the oil by having some fuel dilution and shearing buffer.
If you’re worried about warranty, do not use Mobil 1 ESPx2 0w20. That oil is green, and it’s super obvious that it’s an oil not recommended by Toyota just by the color of it. If anything happens and you gotta go to the dealership, they will see that green oil, and it will raise questions.
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As I mentioned in my "confessions of a Thickie" thread, I've realized that viscosity is a sufficiency thing. I can afford a bottle of Coke, and so can Jeff Bezos. The fact that he's a bit richer than me doesn't alter the fact that we can both sip cokes.
Is the oil thick enough to keep you in hydrodynamic lubrication (near the right on stribeck?), then it's thick enough. Adding viscosity is not adding protection if it means going beyond that point.
My contention-- and why I'm still mostly a "thickie"-- is that the OEMs have all the incentive in the world to compromise wear performance in the name of MPG. It's not that a 0w-20 oil doesn't worth or lubricate well enough to get you through the warranty. It's that the wear performance over the longer term (150k-200k miles) of a thicker grade oil seems to be better.
And even if a 5w30 is perfectly sufficient from a viscosity perspective, going thicker may be desirable for reasons that have nothing to do with viscometrics per se. This is because many formulation limits are tied to viscosity grades, so stepping up to thicker might buy you a stouter additive pack.
A tiny bit of excess viscosity causes no harm. A tiny bit of insufficient viscosity might.
Finally, I'm a strong believer in Pareto logic. Selecting an oil means first starting with the question: what part of the engine that will be the part that wears first to the degree the engine is no longer serviceable? Is it a bearing? Of course not. Camshaft? Almost never.
The single part of the engine most likely to limit the life of the engine is the TRR-- the Top Ring Reversal. Specifically, the top piston ring and its interfaces with the piston and the bore at the TRR. Which means the engine will last the longest if the oil is selected based on what this particular location needs. What does it need?
Well, it needs higher viscosity because the velocity briefly drops to zero. With no relative motion, there is no hydrodynamic lubrication. More viscosity means thicker films at the location where they are most needed.
It also needs utmost cleanliness. Huge fractions of existing bore wear are due to the abrasive wear of carbon deposits that have accumulated.
The second most important item to lubricate is IMO the timing chain (since most cars are chains now). Minimizing chain wear is critical to ensure that rest of the engine doesn't see sudden increases in wear from chain slop or timing shift. So, do chains need thinner or thicker oils? Thicker, obviously. Heck, the ideal chain lube is gear oil (mostly for EP additives, and I know gear oils are actually lower viscosity in some cases...). But more importantly, you need a stout antiwear addpack for chain wear, something lacking in many low-SAPS oils.
So we have a sort of shopping list for the most important oil properties: sufficient viscosity at the TRR, utmost cleanliness in that location, and good EP/AW additives for chains. If the oil satisfies these requirements, then the rest of the engine is happy basically for free. These are "strong requirements" that capture all the other requirements.
Bonus points if it lasts a long time and resists oxidation, etc. It just happens to be that the oils the resist oxidation really well also tend to be cleaner in the hot parts (piston, turbo. and TRR).
Is the oil thick enough to keep you in hydrodynamic lubrication (near the right on stribeck?), then it's thick enough. Adding viscosity is not adding protection if it means going beyond that point.
My contention-- and why I'm still mostly a "thickie"-- is that the OEMs have all the incentive in the world to compromise wear performance in the name of MPG. It's not that a 0w-20 oil doesn't worth or lubricate well enough to get you through the warranty. It's that the wear performance over the longer term (150k-200k miles) of a thicker grade oil seems to be better.
And even if a 5w30 is perfectly sufficient from a viscosity perspective, going thicker may be desirable for reasons that have nothing to do with viscometrics per se. This is because many formulation limits are tied to viscosity grades, so stepping up to thicker might buy you a stouter additive pack.
A tiny bit of excess viscosity causes no harm. A tiny bit of insufficient viscosity might.
Finally, I'm a strong believer in Pareto logic. Selecting an oil means first starting with the question: what part of the engine that will be the part that wears first to the degree the engine is no longer serviceable? Is it a bearing? Of course not. Camshaft? Almost never.
The single part of the engine most likely to limit the life of the engine is the TRR-- the Top Ring Reversal. Specifically, the top piston ring and its interfaces with the piston and the bore at the TRR. Which means the engine will last the longest if the oil is selected based on what this particular location needs. What does it need?
Well, it needs higher viscosity because the velocity briefly drops to zero. With no relative motion, there is no hydrodynamic lubrication. More viscosity means thicker films at the location where they are most needed.
It also needs utmost cleanliness. Huge fractions of existing bore wear are due to the abrasive wear of carbon deposits that have accumulated.
The second most important item to lubricate is IMO the timing chain (since most cars are chains now). Minimizing chain wear is critical to ensure that rest of the engine doesn't see sudden increases in wear from chain slop or timing shift. So, do chains need thinner or thicker oils? Thicker, obviously. Heck, the ideal chain lube is gear oil (mostly for EP additives, and I know gear oils are actually lower viscosity in some cases...). But more importantly, you need a stout antiwear addpack for chain wear, something lacking in many low-SAPS oils.
So we have a sort of shopping list for the most important oil properties: sufficient viscosity at the TRR, utmost cleanliness in that location, and good EP/AW additives for chains. If the oil satisfies these requirements, then the rest of the engine is happy basically for free. These are "strong requirements" that capture all the other requirements.
Bonus points if it lasts a long time and resists oxidation, etc. It just happens to be that the oils the resist oxidation really well also tend to be cleaner in the hot parts (piston, turbo. and TRR).
He didn't introduce himself and announce his first post. Absent that, I'll assume it's another drive-by-and-ghost and they'll get the same amount of social interaction is give any other ephemeral contact.
It might be the single strongest argument for VRP or HPL.
Backpfeifengesicht. Sorry, no English translation.
What company has the best reputation for durability? Answer: Toyota.
What company specs the thinnest oil in the industry? Answer: Toyota.
The "thickies" give me a chuckle. Move from a 20 to a 40 grade oil? What's the basis? Opinion. No science. "Thin oil is about "the epa" or "cafe". No doubt, fuel economy is a factor, but don't kid yourself.
What company specs the thinnest oil in the industry? Answer: Toyota.
The "thickies" give me a chuckle. Move from a 20 to a 40 grade oil? What's the basis? Opinion. No science. "Thin oil is about "the epa" or "cafe". No doubt, fuel economy is a factor, but don't kid yourself.
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5W20 is not going up a grade. 0 & 5W30 would be.
The move towards thinner grade oils is exactly tied to fuel consumption decrease, and this is directly a result of CAFE.
As for a basis, I have a couple. One is wear reduction since an increase in HT/HS always reduces wear. It's not a linear graph but it will decrease it nonetheless. Whether that is important to you or not is up to you.
The second reason is as a mitigation of fuel dilution. The OP's Lexus may or may not suffer from that but my Tiguan does.
It is all about science. The only opinion I've seen is that by some magical way thinner oils are "better" for an engine. They are not, everything about them is a detraction. The only benefit is reduced fuel consumption and that is marginal at best. Here with an increase of two grades it will impact consumption about 2% to perhaps 4% depending on the specific oil. Again that might be important to you, and if it is then that's your choice. But don't chuckle at the thickies because you think thinner oils are better in a mechanical sense. They are not.
Assuming the oil is thick enough to avoid metal to metal contact, increasing viscosity adds no value.
And I certainly hope, trust, that big motor companies like Toyota and Honda are not compromising durability for the sake of CAFE numbers.
Fuel dilution is a question. Honda has put out a white paper in the public domain that suggests they know about fuel dilution, and one would assume, their oil recommendations take this into consideration. That said, I appreciate when someone feels more confident by bumping up an oil viscosity grade. Particularly, when in many parts of the world, said thicker oil is sanctioned by the OEM. Moving up two grades just seems like a purely opinion based decision. To each their own, though.
BTW, I've been mixing 0W-20 with 5w-30 during my most recent oil changes in my oil diluting Civic 1.5T. It's a bit of a chuckle, mixing such as I do, but I can't help it. I have way too much oil, of various grades, in the locker. Gotta use it up somehow! And I don't care what anyone says, I can feel the slight increase in oil thickness in terms of how the engine runs when cold.
Carlostrece
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Wow. The OP asked a relatively simple question. In response he hears about Stribeck curve, etc, debates and science ad nauseum that continues even after people know it's his first post. 
.
To be realistic, how many people quoting detailed science or petroleum engineering charts and details ad nauseum are themselves scientists or petroleum engineers? The hair splitting is excessive. There are many threads where an OP wants to enjoy splitting hairs and discussing and debating science and engineering ad nauseum and that's fine, but in this thread the OP (in his 1st post) just wants advice that's easy to understand and follow.
I'm personal family friends for 45 years with a petroleum engineer and also know another P.E. pretty well for 20+ years. Guess how much time they spend at public oil forums.
There is some good, relatively simple, down to earth advice in this thread that would be easy for a newbie to follow. So thumbs up to those folks.
OP, it's this simple. If you're required to use 0w20 for warranty, choose the thickest available that's not green, purple or any funky color that would raise eyebrows (as member FTTSHO previously said).
Euro oils, and Euro approved oils, are thicker than American oils of same grade. So a Euro 0w20 will be thicker than an American 0w20. In fact, a typical Euro 0w20 is almost as thick as a typical American 5w30. I don't know if your warranty objects to Euro or Euro approved oils. I suspect there are some/several that would be fine with your warranty.
If you want an American oil (which will cost less than Euro) then Pennzoil Ultimate Protection Full Syn (QSUPFS) is the thickest American oil that I know of. By contrast Pennzoil Ultra Platinum (PUP) is the thinnest American oil that I know of. QSUPFS 0w20 is much thicker than PUP 0w20. I say that based on comparing viscosity of virgin and used oil analysis of each oil, which tells how thick they are IRL, which is more accurate than comparing their published data sheets claimed viscosity.
After having said all the above... How would a dealership know if you used a 5w30? Do they have a way to know? If not, then I suggest using PUP 5w30.
.To be realistic, how many people quoting detailed science or petroleum engineering charts and details ad nauseum are themselves scientists or petroleum engineers? The hair splitting is excessive. There are many threads where an OP wants to enjoy splitting hairs and discussing and debating science and engineering ad nauseum and that's fine, but in this thread the OP (in his 1st post) just wants advice that's easy to understand and follow.
I'm personal family friends for 45 years with a petroleum engineer and also know another P.E. pretty well for 20+ years. Guess how much time they spend at public oil forums.
There is some good, relatively simple, down to earth advice in this thread that would be easy for a newbie to follow. So thumbs up to those folks.
OP, it's this simple. If you're required to use 0w20 for warranty, choose the thickest available that's not green, purple or any funky color that would raise eyebrows (as member FTTSHO previously said).
Euro oils, and Euro approved oils, are thicker than American oils of same grade. So a Euro 0w20 will be thicker than an American 0w20. In fact, a typical Euro 0w20 is almost as thick as a typical American 5w30. I don't know if your warranty objects to Euro or Euro approved oils. I suspect there are some/several that would be fine with your warranty.
If you want an American oil (which will cost less than Euro) then Pennzoil Ultimate Protection Full Syn (QSUPFS) is the thickest American oil that I know of. By contrast Pennzoil Ultra Platinum (PUP) is the thinnest American oil that I know of. QSUPFS 0w20 is much thicker than PUP 0w20. I say that based on comparing viscosity of virgin and used oil analysis of each oil, which tells how thick they are IRL, which is more accurate than comparing their published data sheets claimed viscosity.
After having said all the above... How would a dealership know if you used a 5w30? Do they have a way to know? If not, then I suggest using PUP 5w30.
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