Have you even read your manual? Do you have a manual?

This is from my manual on my 2018 LX, (my third LX) and it is pretty specific defining the octane requirements.

 

I use premium in my GS 350 only because I can't get Reg. in non- ethanol. And I can in premium.

 

I wished I bought my oil tanker with me!!! LOL, just kidding.

The gas pump read out was from a previous customer and I took the picture before I gased up. I was almost empty. But I wished the LX570 gas tank was bigger!!

 

No, I haven't been answering as simple question as if it is written somewhere in the manual. I read the manual. I know what is there. I just answered that we will never know the thruth. The question is: Is there a software difference between 5.7 V8 in LX and Land Cruiser? We already know that there is no hardware difference but the engine still can use some different data while running (although probably not).

 

I agree, but you did say it wasn't in the manual. It is in the manual. Does it make a material difference? I'm sure everyone who is a member of this group has a different opinion and I am also sure Toyota will never help us to know the truth.

 

Its hard to believe that the engineers at Toyota are wrong to list what they have listed in the LX manual. In my opinion, the Land Cruiser for the US market is not SAE tested for horsepower ratings, neither is the Tundra 5.7 or Sequoia. The ratings are listed at 381hp. There should be a HP variance due in part to the Land Cruiser full time power-train vs the Tundra part time 4WD powertrain that runs in 2WD. You see a HP variance in every awd vs 2wd set up with the Lexus sedan line up, but not between the Tundra 4WD/2WD and the Land Cruiser full time set up.

Back in 2006, Toyota moved to a SAE based system for testing their vehicles, before that all of the engines were rated without much of their drive-train and accessories included. My 4Runner 4.7 also stated regular fuel is minimum but better performance was implied with premium, the LX and LC at the time required premium fuel....both were rated at 235HP at the time. Then in 06, HP were all over the map with the 4.7 due to SAE testing requirements.

Something has to give IMO. My guess is the LX570 is in fact tuned to run on 91 as it achieves the full 383hp with 91, it says that in the legal disclaimer on Lexus.com for performance numbers.

 

not sure if anyone mentioned this, but here is an article from Edmunds.com. They compiled a list of cars which are recommended to use premium vs cars that are REQUIRED to run premium. So far, the LX570 is not REQUIRED but is recommended.

https://www.edmunds.com/fuel-economy...g-premium.html

 

Interesting and points out the most important fact as far as I'm concerned. Yes, the engine management systems can compensate for lower octane fuel, BUT there will be a decrease in performance.

For years my brother has been ragging me about using premium in my LX's and I've told him that on the highway I really don't want to deal with the performance loss. If you are OK with trying to pass on a two lane road with the reduced performance then have at it. Myself, I'll continue to use premium and achieve the best performance I can with the stock engine.

 

That seems to make sense.

 

Yes, I really worry about the reduced performance. There is a big difference - 2hp (381 on LC vs 383 hp on LX).

 

That's interesting although I worry that it's an error. Lexus clearly specifies that Premium is required. Maybe Edmunds have some different information or they simply read our forum :-)

 

If Edmunds said to do something contrary to what Toyota/Lexus tells you, would you do it? Would you not change your oil at the required interval if Edmunds told you not to?

 

I'd want to take it from the horse's mouth...v. after someone else has "digested" it. Toyota may require it in the north American market for sales-ey reasons, but I'd ask for the 4th or 5th time what happens in other markets, especially the ME where "good" gas can disappear without warning. Not to mention...anecdotally, no one here, on mud, or Lexus owners club have reported engine damage with other than premium; also, no TSB's from Toyota reiterating their opinion on premium only.

 

 

thanks.