Where I am premium is 0.50 more that 87 . Using 15000 miles a year with average 20 MPG that is a lousy 375.00 more a year . 31.00 a month . A Hybrid should do better than that.
If someone is one paycheck away from disaster, perhaps they should not be driving a Lexus!
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Sure, try and bring logic into the conversation.
Exactly. Somehow the simple math and actual numbers of using regular instead of premium are completely lost on the people who ask about using a lower grade gas. No matter how many times you demonstrate that the supposed savings is no more than pocket change, they just donât get it.
Lexus recommends minimum 91 octane
https://lexus2.custhelp.com/app/answers/detail/a_id/8129/kw/Lexus+History+Timeline/related/1
with that, you can decide based on the other comments so far (with the option to ignore the emotions and reactions)
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Nope. The owners manual says ârequired â. And your link says
Use of unleaded gasoline with an octane rating lower than what is listed for your model year vehicle could potentially result in engine knocking. If the octane rating used is less than required, damage to the engine may occur and which could void the vehicle warranty.
IF thatâs the case, then Lexus is not doing anyone any favors by having different wording between its manual and its webpage â please take it up with them, not me.
yes that Lexus webpage says that, which fits with the use of ârecommended minimumâ (twice) on that page
It is the case, see the text from the owners manual I posted earlier.
you probably mean this:
Hereâs what your owners manual says, seems pretty clear:
Premium unleaded gasoline with an octane rating of 91 (Research Octane Number 96) or higher required for optimum engine performance. If 91 octane cannot be obtained, you may use unleaded gasoline with an octane rating as low as 87 (Research Octane Number 91). Use of unleaded gaso- line with an octane rating lower than 91 may result in engine knocking. Per- sistent knocking can lead to engine damage and should be corrected by refueling with higher octane unleaded gasoline.
interesting that ârequired for optimum engine performanceâ is immediately followed by âIf 91 octane cannot be obtained, you may use unleaded gasoline with an octane rating as low as 87â
sounds like Lexus being reasonably consistent (although vague) with its use of ârecommended minimumâ and the additional wording on the webpage
âRequiredâ means ârequiredâ, to me. I think theyâre giving advice when premium is unavailable. Use regular if necessary, fill back up with premium ASAP.
I didnât post the paragraph for the same yearâs RX350. There, premium is ârecommendedâ. So there is a clear difference between the two.
ok, sure. you are free to interpret as you like
although I wonder if you interpret the following two examples differently:
-
âPremium unleaded gasoline with an octane rating of 91 (Research Octane Number 96) or higher required for optimum engine performance.â
-
âPremium unleaded gasoline with an octane rating of 91 (Research Octane Number 96) or higher required.â
#1 is from your comment; #2 is a truncated version which I would interpret differently from #1, especially given the subsequent additional statements as found in your comment
and given how Lexus seems to use different language between its manual and its webpage, the RX350 manual isnât determinative (especially when the wording isnât provided and the webpage provides 87 as ârecommended minimumâ for the 2014 RX350)
But you left out the following two lines which are extremely relevant:
required for optimum engine performance. If 91 octane cannot be obtained, you may use unleaded gasoline with an octane rating as low as 87 (Research Octane Number 91). Use of unleaded gaso- line with an octane rating lower than 91 may result in engine knocking. Per- sistent knocking can lead to engine damage and should be corrected by refueling with higher octane unleaded gasoline.
You canât cherry pick the first two lines out of context.
My 2006 Nissan Pathfinder has the language similar to #1, where 91 is RECOMMENDED for the optimal engine performance, and at least 87 is REQUIRED
ârequiredâ is strong enough to define the minimal accepted value IMHO, ârecommendedâ is not strong in this sense
Subaru WRX has language similar to Lexus, where they define REQUIRED as 91 and then say âif you can not readily obtain 91, you can temporarily use 87, but should avoid high engine load to avoid engine damageâ, something of that sort
I wasnât cherry picking (I quoted the entire passage from T immediately before what you pointed to) â I was focusing on the ârequiredâ language that T was emphasizing
I agree with you and think Nissanâs wording is clearer. Lexus is the one doing this, with
ârecommended minimumâ from its webpage (even with the additional extended wording there) is NOT the same as
"required for optimum engine performanceâ, which is not the same (to me) as
ârequired.â
And as I noted earlier, the Lexus webpage also states 87 as the ârecommended minimumâ for the 2014 RX350 when I strongly suspect that anything under 87 is a no go.
But the provision to use regular does not have the same meaning without the caveat that immediately follows it.
To me it says premium is required. Regular can be used in a pinch but if you continue to do that, engine damage is likely.
Thatâs not a recommendation by my reckoning. Ymmv.
Lexus didnât use quite the right grammar to satisfy @Waterbuff even though the meaning is crystal clear to me.
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Do you know what âknockingâ or âpingingâ sounds like? The pinging tends to occur in certain driving situations, like rapidly accelerating up a freeway on-ramp, or going up a long, steep hill. This mild form of engine-knocking really does make a repeated âpingâ sound, sort of like the sound of hitting a ping pong ball with a paddle. Serious detonation â severe pinging â is much louder & sounds sort of like shaking a can of marbles.
Lexus is dancing around the EPA requirements with respect to owners manual information. The fuel and oil used during the emissions durability test and fuel economy test is the oil and fuel
that must be listed in the owners manual.
The RX450h was certified with the EPA for emissions and fuel economy while operating on premium gasoline for the fuel economy value in an effort to justify the premium price for the hybrid system. The RX350 was certified on regular unleaded to appeal to the common customer.
Vehicles of this century can adapt to lower grade fuels, if they didnât it would be a black mark on the manufacture and we would be replacing engines. I see the fuel receipts in customers vehicles and they are not buying premium gasoline. There are people on this message board that do not use the required gasoline or oil in their vehicles but scoff at others for not following the rules.
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I heard stories when I was a kid from old timers who raised the octane by putting mothballs in the gas tank on their Model T Fords. The spark timing on the Model T could be advanced with a lever on the steering column. Maybe those folks whose cars require premium but donât want to pay the extra price for higher octane fuel might go the mothball route. (I seriously hope nobody tries this on a modern car).