Do 6-cylinder Lexus cars require premium fuel?
- Thread starter Shel_B
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Yes, some do, some don't!
When we had our Lexus RX, the owner's manual allowed for any octane however, it did state that higher octane would increase performance. I never noticed a thing with higher octane except increase cost, worst fuel economy even when driving as I do with lower octane(which is to say, easy) and no extra performance that I could notice when standing on the gas. Maybe newer models are better. I do however notice the performance difference with higher octane in my SIL's BMW at WOT.
When we had our Lexus RX, the owner's manual allowed for any octane however, it did state that higher octane would increase performance. I never noticed a thing with higher octane except increase cost, worst fuel economy even when driving as I do with lower octane(which is to say, easy) and no extra performance that I could notice when standing on the gas. Maybe newer models are better. I do however notice the performance difference with higher octane in my SIL's BMW at WOT.
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Depends, some use the (or used to use) the 2GRFE, I believe the ES350 and RX350, which would use regular octane/fuel. While the GS350 I believe is a more higher performance engine that uses the premium fuel. I believe the IS350 also uses premium.
Now all this^^ was a from years ago 2016 and bellow, I’m not sure about now.
Now all this^^ was a from years ago 2016 and bellow, I’m not sure about now.
For RX350, 2011 requires premium, 2012 and up don't.
I was told by a Lexus Tech (not dealer) 6 years ago, that all tests were conducted with 91 octane.
Premium is NOT required, but there is a warning i the owner's manual not to go below 87 octane.
I use 91 octane not for MPG or performance, but because the additives in the premium keep the engine cleaner.
To each his own.
What does it say in your owners manual? What about the label on the fuel door?
If this is not your current vehicle, then you can look in the owners manual online.
If this is not your current vehicle, then you can look in the owners manual online.
Easier here and the answers here are better and more informative.
If you say so, but reading most of them I would still defer to what the manufacturer states. Plus it's really not that hard.
Of course you use whatever fuel you want, but based on the various discussions I have read on this topic, there is very little if any difference between the detergent additives found in the same brand/station. For example, Shell has a marketing approach such as "premium Shell, now with super atomic additives" which implies that their premium is the only grade with the good stuff, but it is not. They just want you to buy the more expensive gasoline and give them more money. Assuming you are comparing gasolines from the same brand/station, the only difference is the octane rating that you choose. I won't get into ethanol blends found between the various gasoline grades because that is a different conversation.
Our 07 requires 91 but will run ok on 89. It gets best performance and mpg on 93
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I have a 2015 RX350 and it does not require premium. I have run it in it a few times, no difference in power or MPG was noted.
I also have a 2013 LX570 and it requires premium. I don't think it's a life or death scenario, but it was explained by someone who very clearly laid it all out as to why you should use premium in the LX570 5.7L engines and why the Tundra/Sequoia 5.7 engines that are rated with 2 less horsepower don't require it at IH8MUD (Land Cruiser specialty forum).
https://forum.ih8mud.com/threads/fuel-premium-vs-regular.1297437/
I also have a 2013 LX570 and it requires premium. I don't think it's a life or death scenario, but it was explained by someone who very clearly laid it all out as to why you should use premium in the LX570 5.7L engines and why the Tundra/Sequoia 5.7 engines that are rated with 2 less horsepower don't require it at IH8MUD (Land Cruiser specialty forum).
https://forum.ih8mud.com/threads/fuel-premium-vs-regular.1297437/
You are saying that premium has more addatives than regular? That's new to me.
There are several reasons why an engine requires premium gas. The most critical is the compression ratio (CR). The higher the Cr the greater the need for higher octane. Why? Air, as with all other gaseous fluids, get hot when it's compressed. The greater the CR the hotter the air gets. This is exasperated by forced induction (FI) such as turbo- and super-charging. FI causes the air to get hot, hence the need for an inter-cooler. Then this compressed air is compressed again by the engine. So, the air get extremely hot. Add gasoline and you have the conditions for pre-ignition. Pre-ignition occurs when the fuel/air mixture ignites because the air is hot. This is what causes knocking and pinging. The octane rating does not indicate how much energy is in the gasoline. It's an indication of the gasoline's ability to resist pre-ignition.
Modern engine computers us a variety of sensors including knock sensors to determine when the engine is either close to or actually experiencing pre-ignition. The computer has several tools to handle pre-ignition including retarding the spark, retarding the camshafts via variable valve timing and changing the fuel injection timing and duration.
Modern engine computers us a variety of sensors including knock sensors to determine when the engine is either close to or actually experiencing pre-ignition. The computer has several tools to handle pre-ignition including retarding the spark, retarding the camshafts via variable valve timing and changing the fuel injection timing and duration.
Personally, if I stick with a Top Tier brand I see a .5-1mpg difference between the top tier(Chevron, Shell, 76) and the lower tier(Arco and Costco) but a bigger difference(as much as 2-3mpg) with “no-name” gas, primarily Safeway.
If I add in an ounce of Red Line SI-1 or Sta-Bil Marine Formula for every 10 gallons of no-name swill, I’ll see close to “branded” MPG.
It depends on the model and the year. Google is your friend.
We bought a 2019 RX 350 and, despite an 11.8 to 1 compression ratio, regular is specified, and it runs fine on 87.
We bought a 2019 RX 350 and, despite an 11.8 to 1 compression ratio, regular is specified, and it runs fine on 87.
Granted this was 11 years ago, but it showed a difference in 87 vs 92/93. Top Tier insures all grades meet top tier standards, but doesn’t really set a ceiling either. More doesn’t necessarily mean better though, they could easily be using a less concentrated/potent additive for a higher grade or one that has slightly different properties.
https://support.lexus.com/s/article/Which-fuel-grade-shou-8129
Pretty comprehensive list.
Pretty comprehensive list.
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