Hi everyone, I just purchased a "new to me" 2007 Lexus LS460. I did a search on the forum but didn't find anything directly for the LS models on CL. I am wondering (and may be opening a can of worms I understand) on what octane gas you guys use?

I am cognizant the fuel door says use Premium only - however I have seen the light and sold my BMW 5 series - that car also recommended 91 but I would often use 89 (which is readily available in the Midwest).

Knowing I have a relatively high compression motor in this LS, I am thinking of sticking with 89. If I HAVE to use 91 I surely will and am not going to balk at the price difference, just want some opinions from the experts here. Thanks in advance!

 

The car is designed to return optimum power and efficiency running on premium. The knock sensors in the engine retard the timing to compensate for lower octane fuel. This prevents detonation. It will not necessarily hurt the engine to run lower octane but in my opinion the savings is not necessarily worth the reduction in power and efficiency. There are tons of threads discussing this subject but no, it won't hurt the car. When dealing with forced induction I would definitely not run regular or mid-grade.

 

The first year or so I used strictly premium but recently for long trips I’ve been using regular and honestly I haven’t noticed any difference in performance or fuel economy.

 

I run only premium gas...... I am a firm believer that the Lexus engineers know more about the LS engine than I know so I will listen to them.

 

I drove 15 years in my LS400 and a year in my LS460 using regular gas without a problem or miss any power. For the last year I've been using premium but I don't feel any difference. I'll probably stick with premium at least till the stock market crashes again.

 

I'm probably going to hell for admitting this, but I've been running regular gas for over a year in my 460 (I'm a bad bad man).

The only time I can notice a difference is on big hills, it's not as efficient and powerful, but I've managed to retain the same fuel economy and I drive a ton so I figure...hey I'll give it a shot. My commute is pretty flat and easy so I don't notice any difference in performance in my daily 80 mile drive. I've probably saved $400-$500 in the year and change I've been doing it, not earth shattering..maybe it's not even worth it, but like I said, I don't notice a difference with the way I drive anyway. Now if I used the car for spirited driving?? I would only use super.

 

I just had the same fleeting thought tonight as I paid $.50 a gallon more for 93 than 89.

 

The Mazda CX9 lists its HP rating at 250 with 93 octane or 227 with 87 octane. This is about 9% less so a rear wheel drive LS460 that comes in at 386HP drops to 352HP. Its not an apples to apples comparison but something to think about. An AWD LS has 360HP and those owners like their power so I guess it really makes little difference, unless your putting 87 in an AWD and going down to 328HP. Still a lot of ponies though.

 

Thanks everyone for the replies. I am still undecided - my 460 is a RWD. My commute to work is 22 miles each way on relatively flat land and I am at highway speed the majority of the commute. I just put in 91 yesterday - however it was a $.50 difference between that and 89. Again the savings of using even 89 compared to 91 would be good - not sure I would go the 87 route but I feel with the comments here I would be good with 89? Maybe I am wrong in that assumption.

Thanks for the input!

 

I would i have used regular unlead on/off. Premium mostly we have a gas rewards card at place i go so every so often i get it a lot cheaper.

 

if it's 50 cent difference.. i would go midgrade..

 

I was leaning the same way - doesn't seem like much but like anything else, it all adds up. If there is no actual data or negative experiences from continuously running 89 let's say compared to 91 or another higher octane, I feel fine running 89.

I do have some extra 110 that I used in my built SBC (different motorsports application) but that stuff is around $8 a gallon - ha.

 

What’s the price difference between the three grades where you are?

 

Here in NJ it is only a 50 cent difference between 87 and 93. Premium gas does not contain any more additives and in many ways the name gas stations use are intentionally deceiving. I ran 87 for a while in my 430 and the difference was not particularly notable in most situations. In my A8 it is due to the engine having forced induction. If you live in high altitude even more reason to run higher octane to prevent pre-detonation. The new LS will be like this as well.

 

$.50 a gallon is a lot. $10 a tank. ~ $50 a month. $600/yr.