xswl0931

It seems that the LX570 and the LC have the same engine. Similar power and torque ratings that could be differentiated by intake and exhaust differences. Compression ratio is the same. However, the Lexus lists as requiring Premium, while the Toyota lists as needing only Regular. Does anyone know if there is an actual need for Premium?

pemarsh

I bought by 570 from the same person i bought my 470 from. He told me at the time the 470 could run on 87 octane, and thats what i did for 4 years. However, he told me i could not do the same thing with the 570, and it actually did require the premium fuel. Just my $.02

Maybe someone can chime in who has been running 87 or 89 in their 570?

SupraLX570

I was told 93 also. Why cheap out on 87k vehicle?

xswl0931

It's not about cheapening out, but I'm trying to understand from a technical point of view why the difference if the specs on the engines are the same.

Da Hapa

As was the case with the LX470, your LX570 will run w/o any problems on regular unleaded. It won't make quite as much power but the difference probably isn't something you'll be able to feel. You also probably won't get quite as good MPG but again, these things get such ****ty mileage the difference doesn't matter.

The onboard computers on these vehicles automatically adjust timing, etc. of it senses pinging, etc.

xswl0931

I expect the engine to compensate for the difference in octane to prevent detonation. However, that doesn't answer why the LC with the same engine has similar power and torque ratings yet only require regular. Thanks for the replies.

<VENOM>

Simply put the LC is for the more cost conservative Toyota crowd, Lexus is a Luxury car and Luxury cars are usually bought by people who enjoy the better things.

Toyota designed these engines to run on premium, then put the fail safe on them to protect them in the long run, cause not everyone is gonna put quality gas in them.

If you look in any Toyota Owners Manual it usually says, for added performance use premium, your actually suppose to run cars on the highest octane possible.

With that said, watch ur gas mileage, and not just on one tank, do like a consistent 10 tanks, with similar driving patterns, my 03 4.7L V8 got better gas mileage on premium then regular, regular would net me about 300 a tank b4 I refilled and premium for net me 400 a tank before I refilled.

Also be aware that if your running regular and then the dealer wants to offer you a fuel injector service, for say 200 bucks, you just defeated the purpose of using regular so you might as well use premium.

The LX570 is an awesome vehicle and does not deserve to have anything less then premium put in it, and those guys driving Tundras and LC, most use premium, not all, but they say the opposite, it has the same compression ratio as the Lexus, so why don't we use premium.

ige

The one I have runs on 91 octane (bought from the Middle East), and no one told me that info, the manual itself states that the owner should fuel the tank by 91 octane. My 1998 LC (4,7 L) has the same fuel prerequisite as the '09 LX570 I'm driving.

Da Hapa

Similar but not the same. There's the answer. 89 vs. 91 isn't going to make a huge difference in power or torque when you're starting out with appx. 380 bhp.

pemarsh

This controversy has been going on forever...since there has been more than one grade of gasoline.

Conclusion: nobody really knows

<VENOM>

actually no, it's been going on for as long as manufactures have been making ECU's that can adjust for the fuel octane

xswl0931

In the Seattle area, I believe we have 87, 89, and 92. In any case, I suspect that Lexus chose to require Premium since from a marketing perspective, Premium = better and people who buy the LX aren't generally concerned about the cost of gas.

vedia15

conservative toyota crowd?...the Land Cruiser is 80+ thousand dollars...there is nothing conservative about an 80 grand car...trying to down grade toyota owners...when the dude drives a 03 Lexus...I own a 2013 White land cruiser and put regular 87 gas in Bolivia.

ggebhardt

Many might be arguing but I do know. I am on my 3rd LX and they can and do run just fine on regular. I ran premium, mid grade and regular and it is really hard to feel any difference in performance. I do use a good brand of gas (BP) and the LX know no difference. If they is a mileage difference it is very hard to detect.

The bottom line is that it will cost you a additional 4-6 bucks per tank to use a higher octane fuel. If it makes you feel better, by all means do it. If we pay this much for a vehicle, we should do what makes us feel good.

SaniDel

There has to be some reason why Toyota advises some of their customers to use premium gasoline ... otherwise, why make the cost of ownership even higher than it is? It could be simply marketing ... if you buy a premium vehicle you would expect to buy a premium gasoline!

However, I suspect there is something 'technical' ... i.e., non-marketing about Lexus engines that is an advantage over similar Toyota engines, which warrants premium fuel. It may be undetectable in the short-term, but may result in a long-term advantage ... durability, emissions, etc. More to the point ... if the manufacturer specifies it, why would you not do it ... especially during the warranty period?

So, if it "makes us feel good" to follow the manufacturer's specifications, we should ... and I do!
Regards,

SaniDel