Please post your mpg & your oil weight:0w20, 5w20, 0w30, 5w30 or your other choice wt
12-15-14, 04:51 PM
#16
Not to be a stickler for words but the we use words to describe things can create a bit of confusion to the reader. All things being equal the W which means winter will not show a negligible difference, it will not show any difference in relation to measureable mileage on a track.
Last edited by Devh; 12-15-14 at 05:09 PM.
12-15-14, 08:11 PM
#17
0W will save fuel and reduce wear on a cold start (by reaching full oil pressure faster than 5W and reducing the time the oil filter bypass valve stays open, giving unfiltered oil to the engine). Even 0W is too thick during a cold start. Once the engine warms up, there is no difference in viscosity between 5W20 and 0W20. The 0W just thickens less when it is below operating temperature.
So for those who think they are protecting their engine by choosing 5W over 0W....they are doing the exact opposite of what they intend.
So for those who think they are protecting their engine by choosing 5W over 0W....they are doing the exact opposite of what they intend.
08-10-21, 06:50 AM
#18
2007, 119,500 miles, just 2k since delivery from the selling dealership that installed Pennzoil Gold SynBlend 0w20. I plan to migrate to Mobil1 ExtendedPerf HighMileage 5w30 with OCIs under 5k. Vegas, baby! Just too hot for 0w20. No TGMO 5w30 in synthetic.
Earlier comments from Nospinzone, abs, Kennyr44 & Doublebase led me to suspect that this official 20 upper viscosity constraint was yet another Lexus Murica!-only rule … being tied to the US CAFE laws about auto manufacturers hitting fleet-wide MPG targets.
So I just spent an hour looking at Lexus LS460 Owner's Manuals from around the world. Only in the USA & Canada are the choices officially limited to 0w20 & 5w20. In Britain, Ireland & Australia, the owner is directed to choose the viscosity (appropriate to the operating environment) from among 0w20, 5w20, 5w30, 10w30, 15w40 & even 20w50. Even in ever-frigid Finland, Sweden & Norway, owners have access to all these viscosity options … and they were in fact all available in every Manual for the European Market that I opened.
As example, I've attached a copy of the relevant pages from the Irish-version of the 2011 Lexus LS460 Owner's Manual.
Very frustrating. Because of USA CAFE regulations that eternally increase MPG expectations, auto manufacturers are being forced to employ less viscous oil in order to gain greater fuel efficiency … at the expense of less actual engine protection. See https://bit.ly/3CtfrrM . The second graph at that website shows that a 30 upper viscosity oil (with a HTHS somewhat above 3.0) is maximizing engine protection … and at almost twice the rate of protection provided by an 20 upper viscosity oil (with an HTHS of about 2.5-2.7). And check out a few SAE Viscosity Temperature Charts; more than a few suggest that the protection of 20 upper viscosity oil begins to diminish after/around 75°F ambient, while the protection of 30 upper viscosity oil begins to diminish only after/around 95°F ambient. And Internet-searching on "5w20 5w30" brings up on-point many discussions, YouTube videos, etc. on this topic.
Perhaps if we had all been using 5w30 all along, those lower tension rings (also an artifact of CAFE standards) wouldn't be wearing out causing increasing oil consumption after 150k and such.
Best wishes & happy motoring!
Earlier comments from Nospinzone, abs, Kennyr44 & Doublebase led me to suspect that this official 20 upper viscosity constraint was yet another Lexus Murica!-only rule … being tied to the US CAFE laws about auto manufacturers hitting fleet-wide MPG targets.
So I just spent an hour looking at Lexus LS460 Owner's Manuals from around the world. Only in the USA & Canada are the choices officially limited to 0w20 & 5w20. In Britain, Ireland & Australia, the owner is directed to choose the viscosity (appropriate to the operating environment) from among 0w20, 5w20, 5w30, 10w30, 15w40 & even 20w50. Even in ever-frigid Finland, Sweden & Norway, owners have access to all these viscosity options … and they were in fact all available in every Manual for the European Market that I opened.
As example, I've attached a copy of the relevant pages from the Irish-version of the 2011 Lexus LS460 Owner's Manual.
Very frustrating. Because of USA CAFE regulations that eternally increase MPG expectations, auto manufacturers are being forced to employ less viscous oil in order to gain greater fuel efficiency … at the expense of less actual engine protection. See https://bit.ly/3CtfrrM . The second graph at that website shows that a 30 upper viscosity oil (with a HTHS somewhat above 3.0) is maximizing engine protection … and at almost twice the rate of protection provided by an 20 upper viscosity oil (with an HTHS of about 2.5-2.7). And check out a few SAE Viscosity Temperature Charts; more than a few suggest that the protection of 20 upper viscosity oil begins to diminish after/around 75°F ambient, while the protection of 30 upper viscosity oil begins to diminish only after/around 95°F ambient. And Internet-searching on "5w20 5w30" brings up on-point many discussions, YouTube videos, etc. on this topic.
Perhaps if we had all been using 5w30 all along, those lower tension rings (also an artifact of CAFE standards) wouldn't be wearing out causing increasing oil consumption after 150k and such.
Best wishes & happy motoring!
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