My LX570 owners manual states "Premium fuel required" . Some LC owners indicate this is not the case with their LC manuals. Also both LX570 and 200 series Landcruier owners state they only use unleaded regular. I'm asking this question to determine if using 87 octane in my 2011 LX570 would damage or shorten the engine life? Has anyone experienced knocking using unleaded regular in their 5.7 LX - LC engines?
5.7 LX - LC fuel - Regular or Premium?
- Thread starter SWUtah
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gaijin
GOLD Star
The manual for my 2013 LC states:
Fuel
Fuel type Unleaded gasoline only
Octane rating 87 (Research octane number 91) or higher
Fuel tank capacity 24.5 gal. (93 L, 20.4 Imp.gal)
(Reference)
I normally burn Premium (91 Octane), but on a couple of long trips I used 87 Octane regular with no knocking.
Those are the facts, now for the conjecture:
The LX 5.7L engine has a higher horsepower spec than the LC 5.7L engine - it's only a couple of HP, but it is different. My guess, and I emphasise guess because I have no data to back it up, is that in order to guarantee the higher HP spec, Premium (91 Octane) fuel must be used. I further guess that when premium fuel is used in the LC engine, the HP output is the same as the LX engine. So why do Toyota spec the engines differently? My guess is that it is simply marketing - the Lexus engine is presented as having more HP than the LC engine.
So ... my last guess is that you will do no harm and experience no knocking if you decide to burn 87 Octane gasoline in your LX. The engine management computers are very capable of preventing knock when 87 Octane is used.
HTH
Fuel
Fuel type Unleaded gasoline only
Octane rating 87 (Research octane number 91) or higher
Fuel tank capacity 24.5 gal. (93 L, 20.4 Imp.gal)
(Reference)
I normally burn Premium (91 Octane), but on a couple of long trips I used 87 Octane regular with no knocking.
Those are the facts, now for the conjecture:
The LX 5.7L engine has a higher horsepower spec than the LC 5.7L engine - it's only a couple of HP, but it is different. My guess, and I emphasise guess because I have no data to back it up, is that in order to guarantee the higher HP spec, Premium (91 Octane) fuel must be used. I further guess that when premium fuel is used in the LC engine, the HP output is the same as the LX engine. So why do Toyota spec the engines differently? My guess is that it is simply marketing - the Lexus engine is presented as having more HP than the LC engine.
So ... my last guess is that you will do no harm and experience no knocking if you decide to burn 87 Octane gasoline in your LX. The engine management computers are very capable of preventing knock when 87 Octane is used.
HTH
you can use 87 or 91+ , this is what you need to know. I live in Idaho our elevation in 2000ft and the temperatures cooler so 87 is just prefect, but if I take my rig to Arizona I will put 91+ - but for the general public who care not about elevation or outside temperature I suggest 91+
- Thread starter
- #4
So I fill up every 150 miles I guess one time 87 the next 93. Should come out around "90" 
I run my LX on 87 / regular. Haven't had any issues. Occasionally I will run premium through it just in case there are better detergents in the more expensive fuel. 42k miles and no issues on regular.
I ran my 100 on regular all of its 331k miles. Never had any issues even if it too said 'Premium Required'.
I ran my 100 on regular all of its 331k miles. Never had any issues even if it too said 'Premium Required'.
- Thread starter
- #6
You every hear any knocking? What altitude and climate do you live in? Thanks for the input.
I live at 1800 feet, although I have done many trips through the Rockies and Sierra with zero issues. I drive it pretty easy though.
You can use either, the computer will retard timing and adjust fuel air/mix ratio.... Simple rule is the lower octane will give less horsepower more octane will allow the engine to run at its full potential. Either is fine... Octane is basically the resistance to detonation...
Cars that only require 87 will get no advantages running higher octane.
Back in the day when they ran high horse power cars with out knock sensors and computers a random detonation with low octane gas meant kaboom!!! A Piston going up and a random explosion pushing the rod down before it was ready to go down was basically cause for a new engine.
It's all about compression and the timing of the spark relative to the position of the piston and rod.... New cars pretty much prevent all this complication
Cars that only require 87 will get no advantages running higher octane.
Back in the day when they ran high horse power cars with out knock sensors and computers a random detonation with low octane gas meant kaboom!!! A Piston going up and a random explosion pushing the rod down before it was ready to go down was basically cause for a new engine.
It's all about compression and the timing of the spark relative to the position of the piston and rod.... New cars pretty much prevent all this complication
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I have noticed both on my 100 and now the 200 with a premium tank I get about 1-2 more MPGs on the highway...maybe coincidence, maybe I drove slower...
I've never understood people stressing about paying for 'premium' fuel in their vehicles.
Is $3 a tank worth any possible risk to damaging your $80,000 vehicle?
Same goes for the people who sit in line for an hour at Costco to get gas because it's a few cents per gallon cheaper. My time is worth more then the savings.
Is $3 a tank worth any possible risk to damaging your $80,000 vehicle?
Same goes for the people who sit in line for an hour at Costco to get gas because it's a few cents per gallon cheaper. My time is worth more then the savings.
i like this dude
Here's why I want to know. I happen to drive down Mexico way, if not farther south, once a year or so. I often buy fuel so poor that I filter it through multiple coffee filters before it goes in the tank. With my 100 I had zero issues through the years running on any gasoline that I could find but I am curious about the directive that the Lexus requires premium. Why is it 'required'? Lord knows I don't need all that horsepower so if it's just that then I will continue to run any gas I can. If not, what else?
- Thread starter
- #14
I gave up and use Exxon 93 octane.
bjowett
Supporting Vendor
The Tundra, Land Cruiser, and LX570 all use the same 3UR-FE engine with the same 10.2:1 compression ration. They will all run good on 87 octane, and probably run fine on the poor fuel Patrick mentions. Toyota specs a minimum 91 octane for Tundra 3UR FE equipped with the TRD Supercharger. That's 10.2:1 with about 7 psi being shoved down its throat, or an absolute compression ratio of about 15:1.
Welcome to the site TestLap.
The Lexus (drinks Stella Artois at NYC prices and brags about it) has so many unnecessary electrical doo dads to weigh it down compared to the hairy chested Land Cruiser (drinks PBR and Craft Brews*) that it requires the higher octane to push itself along.
Or some such or anther.
*and probably smoke good pot too....
- Thread starter
- #18
I tell my wife I use regular and then pump 93 octane. Yes it is sad that is about as exciting as it gets in my life. Don't take that away from me with this talk of everything being fine on 87.
$2.49 here in Ohio. I may need to take a long road trip.
