Ls400&ls430: Is It Safe To Fill Regular Unleaded

[mttls400]

Hello Everyone,

I did fill up both ls400 & ls430 tank with regular unleaded last week - but i am wonder that it will hurt the engine in the long run. Please, comment

Michael

[RFeldes]

No hurt I am aware of, only lost gas mileage.

[wwest]

Hello Everyone,

I did fill up both ls400 & ls430 tank with regular unleaded last week - but i am wonder that it will hurt the engine in the long run. Please, comment

Michael

Our '92 LS400, ~130,000 miles, has been fueled with regular from the get-go.

Knock sensors....

[cjmeyer]

Have been running my 95 on regular and don't hear any knocking.

[GKLCPA]

If you're in California, I don't blame you for taking the cheaper option. Even with that, you're still probably paying north of $ 4 a gallon according to an article I read today.

I alternate between regular and premium depending upon when I can find gas at a reasonable price. Using regular has had no ill effects that I can tell other than a slight loss of power and slightly less mpg.

[dscabicky]

I run my 1990 LS400 (110K) on regular. May be a slight loss of horsepower I'm told (I don't notice anything) but not in mileage. Cars on-board computer adjusts to lower octane.

[eatingupblacktop]

The discussion about reg vs prem has been ongoing for a long time and there are many threads on this topic. What I haven't found yet is a verifiable analysis with hard numbers comparing the difference in cost and the difference in mileage to show which one has the lesser net cost.

With gas prices headed skyward, I think there will be many more drivers considering their options. Regular or premium, ganging up on errand runs, car pooling, changing driving habits, less idling, higher tire pressures, moving back into city cores, motorcycles, scooters, bikes, walking, even staying at home instead of going out. Our lifestyles are in for major changes and as Henley sang in "Boys of Summer" - "You can never go back" or as Dylan sang some time ago but applies even more so today, "The times they are achangin". Anyone for nostalgia?

[PilotguyPA28]

The decrease in mileage isn't worth the cost savings.

[T-Bone Mike]

I'm told by a reliable source that the reason to run premium when recommended vs regular (computers and kinock sensors accomdate that change) is a moisture issue. Apparently in the long term, an engine set to burn premium will accumulate less moisture in an engine when run on premium than on regular. Engines, of course can rot from the inside even when performing fine on a particular tank of gas. Since learning that, I run my 2000 LS on premium only and these days just try to grin and bear it at the pump as my fillups approach the $100 mark here on Long Island. Anyone know anything about this moisture issue?

[cjmeyer]

I'm told by a reliable source that the reason to run premium when recommended vs regular (computers and kinock sensors accomdate that change) is a moisture issue. Apparently in the long term, an engine set to burn premium will accumulate less moisture in an engine when run on premium than on regular. Engines, of course can rot from the inside even when performing fine on a particular tank of gas. Since learning that, I run my 2000 LS on premium only and these days just try to grin and bear it at the pump as my fillups approach the $100 mark here on Long Island. Anyone know anything about this moisture issue?

Yikes!I am about to make a trip to the Island on Monday! :o

[MyPGAQuest]

I do not know about knocking or anything like that, but someone told me that my 2000 LS400 requires 91 octane so I alternate between the 89 and 93 every time I fill up. I have not noticed any problems thus far. Am curious though...

Todd

[midapo]

Don't know how much it applies to a Lexus, but this was kind of interesting on yahoo: http://finance.yahoo.com/family-home/artic...as-Saving-Myths

[SKperformance]

please do a search for previous threads , this type of question has more opinions than facts.