Who's the first to put regular octane gas on their GX550?
- Thread starter spiderjoe
- Start date
Modern engines typically employ knock sensors to eliminate pre-detonation. Not the case?
I view that as an insurance policy. And I don’t want to be using that unnecessarily all the time.
That said I might be an outlier in this group because I use this car only on the weekends and I’ll likely put less than 5000 miles a year on it so my gas costs are negligible versus those using it as a daily driver.
Good point. Retired, we only do about 4K miles/year. I suppose it grinds on me that a modern engine allegedly cannot accommodate various octane values, albeit reducing the performance a tad.
No one said it can’t accommodate. It absolutely can. However every trade off has a price.
The engine was designed to use high octane gas, operating outside of its design parameters will result in unoptimal performance. That might be excess wear and tear, higher fuel usage, lower performance, rough running, or some combination of all of the above.
If you are stuck in the middle of nowhere and all you have available is 87? Use that and don’t lose sleep over it. if you are in the middle of the city then use what the engine asks for.
You could also try using the wrong oil in the car to save a couple bucks? Same trad3 offs as above, heck it will even still run. Wouldn’t reccomend it long term.
The engineers who designed the car made choices for a reason, unless you have a strong rationale otherwise I reopened taking their recommendations at face value.
I cannot buy off on "excess wear and tear", but yes, some valid points.
Only reason the manufacturer recommends premium is to meet their power and mileage claims. You can use regular. Yes their will be less power, hardly noticeable, and yes a little less mileage, hardly noticeable. But the computer will take care of any possible detonation.
Friend that works at Lexus dealership said the computer will adjust to regular gas. Not a problem.
I have a 2014 GX and have always used regular gas and I’m at 190,000 milesWith debates on oil change intervals elsewhere, here is another pointless one, who has ventured into using regular 87 octane gasoline on their GX550? Keep it friendly please
On the Toyota Land Cruiser site this is a HOT discussion. Agreed, the computer will adjust for regular gas.
As someone that's calibrated engines, I would highly recommend against regularly using lower octane fuel. While it's true the ECU has ignition timing and boost tables to compensate for knock and other adverse conditions, you don't want to constantly rely on that to keep the engine safe. This is especially true under higher load conditions like rapid acceleration or towing.
Keep in mind that all else being equal, (e.g. air and coolant temps) the knock sensor(s) have to detect knock before the ECU reduces ignition timing. So there's a real chance of premature wear and/or damage if that's regularly happening.
On maximum effort racing applications, "riding the knock sensor" can allow the engine to run closer to MBT but that's not a strategy for a daily driven car where the operational target is 150k+ miles. Can you run lower octane fuel occasionally and get away with? Sure. There's just little reason to do so.
Finally, the GX550 is priced between 65k - 83k. If the small additional cost of premium fuel is too much for your budget, then you bought the wrong car.
Keep in mind that all else being equal, (e.g. air and coolant temps) the knock sensor(s) have to detect knock before the ECU reduces ignition timing. So there's a real chance of premature wear and/or damage if that's regularly happening.
On maximum effort racing applications, "riding the knock sensor" can allow the engine to run closer to MBT but that's not a strategy for a daily driven car where the operational target is 150k+ miles. Can you run lower octane fuel occasionally and get away with? Sure. There's just little reason to do so.
Finally, the GX550 is priced between 65k - 83k. If the small additional cost of premium fuel is too much for your budget, then you bought the wrong car.
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I haven't cross-referenced the available data but I think it would be interesting to know if a person who wants to save a few dimes on a gallon of gas is the same type of person who changes their oil every couple thousand miles "just to be safe".....
Probably no correlation. I only run 93 octane in my GX and I change the oil every 3 - 5k miles. Much of my driving is shorter trips which contaminates the oil more quickly.
They problem is 80% of the population think premium fuel is a scam invented by big oil to rip them off.
There is no convincing these types of people.
I haven't owned a car that doesn't take premium fuel for a decade or more.
Where I live, Premium can be about $1 more per gallon. Regular a bit over $3, Premium near or over $4. Just because you can afford a $70K car and thus can afford Premium doesn't mean you want to pay that much extra if you don't have to. It's also a consideration for long road trips where availability might be an issue or cost differences especially high at whatever station you end up having to use. One issue in some states is that 91 Octane is the highest you can get. Now that's fine for the GX per Lexus, but it's not fine for some other cars (like my GR86) especially in hot weather. It really wants 93 or you risk knock.
So I don't blame anyone for wanting to run regular. It's one of the many things I like about my 4Runner.
Now, on the question of whether Regular would actually do any damage to the GX.... Toyota specs Regular for the Tundra, which uses the same engine. So why does the GX need Premium?
So I don't blame anyone for wanting to run regular. It's one of the many things I like about my 4Runner.
Now, on the question of whether Regular would actually do any damage to the GX.... Toyota specs Regular for the Tundra, which uses the same engine. So why does the GX need Premium?
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