More Fuel for the Ever-Raging 20wt Oil Debate
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The problem is of course we have no way of knowing what the real logic behind these statements was. Would an Xw-20 operated "at high speeds, or under extreme load conditions" show up as extra wear when compared to an Xw-30 in a UOA?
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Oil temp is related to load in my experience. Highway is your highest level of combustion input per minute and without some exchanger or cooler, your oil temp is going to show the increased throughput in elevated temp. Your cooling system (typically) won't. Your oil temp isn't typically regulated ..your coolant temp is.
I would think that the higher load usage would result in consumption. You're looking at very little difference in visc at elevated temps.
I would think that the higher load usage would result in consumption. You're looking at very little difference in visc at elevated temps.
Originally Posted By: rationull
This brings the question to my mind though, if Xw-20 were "poorly" suited to certain driving styles, would that fact show itself in UOAs or only in an engine teardown?
Or on the dipstick?
Toyota doesn't want someone who drives in severe conditions to accidentally go below the "ADD" mark so for folks who never check the level, give them a 30 weight.
This brings the question to my mind though, if Xw-20 were "poorly" suited to certain driving styles, would that fact show itself in UOAs or only in an engine teardown?
Or on the dipstick?
Toyota doesn't want someone who drives in severe conditions to accidentally go below the "ADD" mark so for folks who never check the level, give them a 30 weight.
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If my bearing (and other) clearances where narrow (.00015 ish), a thick oil might be catastrophic...
And nice to see they fixed the manual... My 07's manual is awful.
And nice to see they fixed the manual... My 07's manual is awful.
Last year the engine used Xw-30 and had it on the cap..is the engine that much different this year that the bearing differences would have been altered?? What did they do, added dual VVT and got rid of the power steering, the rest of the engine is pretty much the same.
I've been using PP 5w30 with a Motorcraft filter in my '08 Mustang GT. The engine is noticeably smoother and quieter with it, though I took about a .5mpg mileage hit. The car is manual shift, so I figure having an HTHS of 3.0 instead of 2.6 is a plus if I run it hard or accidentally lug it a bit.
I'll be doing a UOA when the car hits 20K miles. I'm expecting excellent results.
I'll be doing a UOA when the car hits 20K miles. I'm expecting excellent results.
Originally Posted By: Bookmaker
I've been using PP 5w30 with a Motorcraft filter in my '08 Mustang GT. The engine is noticeably smoother and quieter with it, though I took about a .5mpg mileage hit. The car is manual shift, so I figure having an HTHS of 3.0 instead of 2.6 is a plus if I run it hard or accidentally lug it a bit.
I'll be doing a UOA when the car hits 20K miles. I'm expecting excellent results.
It's not a bad idea giving yourself a bit of extra cushion with the 30 grade. 30 grade oils in my Honda do seem to quiet down what is already a very quiet motor, just a tad.
I've been using PP 5w30 with a Motorcraft filter in my '08 Mustang GT. The engine is noticeably smoother and quieter with it, though I took about a .5mpg mileage hit. The car is manual shift, so I figure having an HTHS of 3.0 instead of 2.6 is a plus if I run it hard or accidentally lug it a bit.
I'll be doing a UOA when the car hits 20K miles. I'm expecting excellent results.
It's not a bad idea giving yourself a bit of extra cushion with the 30 grade. 30 grade oils in my Honda do seem to quiet down what is already a very quiet motor, just a tad.
The only advantage to running a 20wt in FL is marginally better fuel efficiency. I'd run the Mobil 1, 0w-20 and say their 10w-30 back to back and compare subjective performance: fuel efficiency, oil consumption, NVH and wear rates through oil analysis.
The reason for comparing two oils with the same basestock type and additive chemistry is to isolate viscosity as the only independent variable in the test.
The reason for comparing two oils with the same basestock type and additive chemistry is to isolate viscosity as the only independent variable in the test.
If TOYOTA let BitOG write the manual, do you think it would be much better....for the lay consumer?
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Originally Posted By: Audi Junkie
If TOYOTA let BitOG write the manual, do you think it would be much better....for the lay consumer?
No. You'd need a "basic" section for the consumer and a "BITOG level complicated" section. That would be broken up into sub-groups.
Tribologist/engineer (not all engineers will automatically qualify for this level)
Tribologist wannabe
Those that know enough that they don't know enough
Those that think that they know enough and don't know that they don't.
If TOYOTA let BitOG write the manual, do you think it would be much better....for the lay consumer?
No. You'd need a "basic" section for the consumer and a "BITOG level complicated" section. That would be broken up into sub-groups.
Tribologist/engineer (not all engineers will automatically qualify for this level)
Tribologist wannabe
Those that know enough that they don't know enough
Those that think that they know enough and don't know that they don't.
I just about [censored] myself laughing!
Manual: "And once you're done over-analyzing our engine clearances, just go grab any 5w-20 out of your stash."
Wow, I can't believe there is no comment on the above EPA document.
Basically, in order to use 5w20 oil in EPA fuel economy tests, manufacturers must:
1. State to consumers that it is the ONLY oil they can use.
2. Force their dealer network to push the use of 5w20.
3. Force quick change shops to use it.
4. Print the requirement on the oil filler cap
or they can't use 5w20 in testing. Any ambiguous statements or viscosity charts in the owner's manual and the manufacturer is disqualified from using it.
It's not what's best for the car that drives 5w20. It's what's best for the manufacturer in meeting CAFE regulations.
The above document spells it out completely...almost like a conspiracy...
Basically, in order to use 5w20 oil in EPA fuel economy tests, manufacturers must:
1. State to consumers that it is the ONLY oil they can use.
2. Force their dealer network to push the use of 5w20.
3. Force quick change shops to use it.
4. Print the requirement on the oil filler cap
or they can't use 5w20 in testing. Any ambiguous statements or viscosity charts in the owner's manual and the manufacturer is disqualified from using it.
It's not what's best for the car that drives 5w20. It's what's best for the manufacturer in meeting CAFE regulations.
The above document spells it out completely...almost like a conspiracy...
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Get your tinfoil hats, boys!
Originally Posted By: firemachine69
Get your tinfoil hats, boys!
Spoken like a true 5w20 lemming...
Get your tinfoil hats, boys!
Spoken like a true 5w20 lemming...
That doesn't mean xw20 oil is bad for engines.
That doesn't imply that you should use xw30 where xw20 is stated.
That is just explaining what manufacturers have to do to certify xw20 for their engines.
Depending of your use, your location, and your mind set on oils, you are free to do whatever you want, it is a free country.
The only things you cannot do if you don't follow the manufacturers recommendations are asked a free rebuild if the engine failed and complained that you cannot achieve the fuel economy listed when you bought the car.
That doesn't imply that you should use xw30 where xw20 is stated.
That is just explaining what manufacturers have to do to certify xw20 for their engines.
Depending of your use, your location, and your mind set on oils, you are free to do whatever you want, it is a free country.
The only things you cannot do if you don't follow the manufacturers recommendations are asked a free rebuild if the engine failed and complained that you cannot achieve the fuel economy listed when you bought the car.
Originally Posted By: Bookmaker
It's not what's best for the car that drives 5w20. It's what's best for the manufacturer in meeting CAFE regulations.
I don't think that logically follows from the document. The document merely states what must be done in order to use 5w-20 oil in the EPA FE tests. There's nothing forcing any manufacturer to actually use 5w-20 oil in applications where it's not sufficient for engine protection.
Take Honda specifically. I highly doubt that if Honda was spec'ing 5w-30 for all the vehicles it specs 5w-20 for, it would fail to meet CAFE requirements. (Maybe I'm wrong, I don't know for sure). Thus, Honda probably isn't being "forced" into recommending only 5w-20 oil.
Further, both Honda and Ford continue to spec 5w-30 in some vehicles (Civic SI and Mustang V6, for instance). So presumably engineering decisions are still impacting the decision of what oil grade to recommend for a given application.
The only thing that document provides is a guarantee that manufacturers cannot spec a 5w-30 oil for actual field use but use a 5w-20 in testing despite not being robust enough.
It's not what's best for the car that drives 5w20. It's what's best for the manufacturer in meeting CAFE regulations.
I don't think that logically follows from the document. The document merely states what must be done in order to use 5w-20 oil in the EPA FE tests. There's nothing forcing any manufacturer to actually use 5w-20 oil in applications where it's not sufficient for engine protection.
Take Honda specifically. I highly doubt that if Honda was spec'ing 5w-30 for all the vehicles it specs 5w-20 for, it would fail to meet CAFE requirements. (Maybe I'm wrong, I don't know for sure). Thus, Honda probably isn't being "forced" into recommending only 5w-20 oil.
Further, both Honda and Ford continue to spec 5w-30 in some vehicles (Civic SI and Mustang V6, for instance). So presumably engineering decisions are still impacting the decision of what oil grade to recommend for a given application.
The only thing that document provides is a guarantee that manufacturers cannot spec a 5w-30 oil for actual field use but use a 5w-20 in testing despite not being robust enough.
Originally Posted By: Bookmaker
Any ambiguous statements or viscosity charts in the owner's manual and the manufacturer is disqualified from using it.
Besides, doesn't this kind of clash with the posted manual photos? If the manual says to use 5w-30 in some situations then we have to assume one of the following:
1) We're misunderstanding the EPA requirements.
2) The EPA requirements have changed.
3) Toyota used 5w-30 for EPA testing in the Camry.
4) Toyota's about to get in trouble.
I highly doubt (4) is the case. (1), and (2) would mean that document is no longer relevant as it's being discussed. (3) would mean that Toyota is spec'ing Xw-20 oil for field use in the absence of influence from EPA testing requirements (implying that the 20 grade oil is up to the task).
Right?
Any ambiguous statements or viscosity charts in the owner's manual and the manufacturer is disqualified from using it.
Besides, doesn't this kind of clash with the posted manual photos? If the manual says to use 5w-30 in some situations then we have to assume one of the following:
1) We're misunderstanding the EPA requirements.
2) The EPA requirements have changed.
3) Toyota used 5w-30 for EPA testing in the Camry.
4) Toyota's about to get in trouble.
I highly doubt (4) is the case. (1), and (2) would mean that document is no longer relevant as it's being discussed. (3) would mean that Toyota is spec'ing Xw-20 oil for field use in the absence of influence from EPA testing requirements (implying that the 20 grade oil is up to the task).
Right?
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