Premium fuel ? (1 Viewer)

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I am probably going to get a YotaWerx tune package for my GX, with an 87 octane tune for normal use and a 91 octane tune for pulling our camper (when more power would be always nice).

FYI, I usually run Top Tier gas in almost all of our vehicles unless I'm in a pinch where I need fuel and only off-brand stations are around. Then I add a bottle of Techron at every oil change to keep things clean. My previous 13:1 compression Mazda 3 did definitely not like cheaper fuel - although I have not noticed any difference on our lower-compression vehicles.
Ummm... I was unaware this is even a possibility.

Interested....
 
Ummm... I was unaware this is even a possibility.

Interested....
They are also offering GX460 tunes.....a couple of other people have had theirs tuned on this forum. I'm not aware of any 470s that have been tuned yet but am willing to guinea pig mine :)
YotaWerxTuning@gmail.com
 
It's not as complicated as you think.

The computer will protect your engine from knocking caused by 87 octane gas. It will also reduce maximum power, especially under load or in high heat environments.

You will get slightly worse MPG running 87 than running 91.

You will get better detergent additives running premium at most brands.

I am normally a relative cheapskate when it comes to cars. But my local station has premium (93 octane) at only 10% higher than 87 octane, so for the increased power, MPG and better additives, plus the probability that we'll own this vehicle for at least a decade, if not more, I've decided on premium.
I think you are right.

BTW around here, 91 is 60 cents more than 87, and 93 is about 80 cents more. If it was only 10% like you have, I would probably be happy with premium too and not worry about it. When I really start to feel it is when I head on a trip across the Great Plains to the Rockies or other points west, which I do several times a year. When filling up several times in one day, it starts to add up.
 
I get slight better MPG with premium than regular. Tested it a few times, never had a knocking problem tho.
I have a CC that gives me 5% cash back on gas purchases so that mitigates the added cost of premium gas 😬
 
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i have always run 91. i ran 87 once on half a tank and i literally threw a code for engine misfire like 20 miles into that tank and my gx went into limp mode. i used my scanner to clear the code, filled the rest of the tank with 91, and have run 91 since.

i have never had any other engine codes in this thing before or after that incident.

really didnt think the rig would be so sensitive to fuel type considering the shared engine with the tundra. im not an engineer and have no idea why this thing requires premium - but i know for a fact that MINE does.
 
I’ve had mine almost a year now and put almost 10k miles on it. (Secondary vehicle) Always used 87, never an issue. It was a off lease buy and I doubt the original owner put premium in it.
I’ve had a 4.7 V8 4runner for four years and it’s always had 87. I’m very close to sea level also.
 
I have an 2008 and a 2013 , 87 in both tanks , .
Got a buddy who worked for Toyota for 25 years as a mechanic , says 87 no problem .
I am not a fan of additives , emotional purchases says another mechanic friend :)
 
I have an 2008 and a 2013 , 87 in both tanks , .
Got a buddy who worked for Toyota for 25 years as a mechanic , says 87 no problem .
I am not a fan of additives , emotional purchases says another mechanic friend :)
That is pretty outdated advice. I work hands on with engine calibration and know a lot of competent mechanics; they are not all of equal skill and often times are not knowledgeable of ECM control. Not to mention no mechanic has full access to the ECM maps, even HP tuners or VF tuner doesn't have full access; they only have access to whatever PID/DID channels they are aware of. There are 40-80,000 variables in todays software that all manage your engine and differentiating between an algorithm issue and calibration issue is not even in a mechanics wheelhouse of knowledge. Just because it won't harm the engine immediately doesn't mean it is "no problem". Should read my post I linked on Page 1 if you want to learn more.

87 on the 460 without recalibrating the base hi table will knock and reduce fuel economy on average. Sure it will run, but you will be in between your base hi and base lo which will throttle your knock counts, but inherently it will knock more than if you use premium. Even premium fuel will knock now and again, it's all risk assessment. If you think saving a few dollars is worth the risk then you do you, but what I found when I put 87 in was it knocked quite a bit and reduced my FE by 1-2mpg which negates the price difference between 87 and 91+ over the course of a tank anyways. I'm sure some engines might tolerate 87 better than others, but for an overall fleet average most everyone will exhibit the same results with a few outliers that might tolerate lower octane better.

Of course every state and local municipality also has different fuel blends, so it could also be a regional anomaly where you may have higher octane than labeled or just a better blend than others. There are a lot of factors that contribute and giving blanket advice as if all fuel is the same throughout the US is a bit of a false positive assumption.

The fact is that the ECM is calibrated for premium fuel, you will knock with less than 91 octane, but if you feel like it is worth the risk then go for it. It will reduce your engine life but there is not a tangible way to assess this or number to give. If you keep up with maintenance and general care, don't drive it hard or put it in high temperature towing environments you probably won't damage it beyond repair. If it lasts 250k instead of 300k, no one is going to be able to attribute said failure to knock without a full teardown where the engine didn't fail catastrophically. Those are beyond engineered lifetimes anyways; Toyota's validation requirements are 150-200k miles depending on the vehicle.
 
87 on the 460 without recalibrating the base hi table will knock and reduce fuel economy on average. Sure it will run, but you will be in between your base hi and base lo which will throttle your knock counts, but inherently it will knock more than if you use premium. Even premium fuel will knock now and again, it's all risk assessment. If you think saving a few dollars is worth the risk then you do you, but what I found when I put 87 in was it knocked quite a bit and reduced my FE by 1-2mpg which negates the price difference between 87 and 91+ over the course of a tank anyways. I'm sure some engines might tolerate 87 better than others, but for an overall fleet average most everyone will exhibit the same results with a few outliers that might tolerate lower octane better.
What bugs me about this is the Tundra used the same engine rated for more power/torque, and does not require premium fuel. Economy is marginally lower on the Tundra but I'd expect that's more to do with aero/weight/tire differences.
 
What bugs me about this is the Tundra used the same engine rated for more power/torque, and does not require premium fuel. Economy is marginally lower on the Tundra but I'd expect that's more to do with aero/weight/tire differences.
Lexus vs. Toyota customers. All the brands do it to squeeze out an extra 10-20hp so they can nudge out the competition as if consumers care. Probably one of the things that sucks when cross shopping with Lexus.
 
What bugs me about this is the Tundra used the same engine rated for more power/torque, and does not require premium fuel. Economy is marginally lower on the Tundra but I'd expect that's more to do with aero/weight/tire differences.
I'm wondering if it's due to differences in the air intake/induction system or exhaust. The Tundra certainly has a bigger engine bay and more room to route the exhaust, maybe it's just more efficient than the more cramped GX platform.
 
My partial point on fuel and other additives is that .
You may feel a difference in power using 91 , however , there may be no real difference , just the expected one .
There's a reason there are soo many additives available , there are soo many people who see or feel the difference , it's the power of a label .
 
Well, I ordered a 23 GX460 last week, it should be here the first week of March. I will be running 93 through it, I have a Sam's Club down the street from me and their price is about the same as 87 at WaWa, and overall, I will only be putting less then 10k miles a year on it expect for a few road trips we are kicking around.
 
Unless someone else mentioned it, combustion temps are lower with premium fuel all else being constant. Also octane less of an issue at high elevations, high elevation areas rarely have more than 91 at the pumps. That said if I owned one I would run premium. I love the longevity.
 
My partial point on fuel and other additives is that .
You may feel a difference in power using 91 , however , there may be no real difference , just the expected one .
There's a reason there are soo many additives available , there are soo many people who see or feel the difference , it's the power of a label .
I wouldn't discount it all the way. For instance we used to use Marathon gas in our lab and we had to stop because the additive package caused a black tar buildup inside the combustion chamber, block and head. Switched to Shell and we don't have those issues anymore. Marathon is labeled as a Top Tier brand too, so I'm sure you can extrapolate that to a cheaper tier gas brand. It's not so much a 1 tank issue, but constant fueling with low quality fuel. There's a lot of blends, Northern US has higher ethanol content in winter gas, AZ/NV/CA has low RVP fuel (lower propensity to combust), Denver has lower octane for altitude, almost every mass metro area has a smog regulatory fuel.
 
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87 on the 460 without recalibrating the base hi table will knock and reduce fuel economy on average. Sure it will run, but you will be in between your base hi and base lo which will throttle your knock counts, but inherently it will knock more than if you use premium. Even premium fuel will knock now and again, it's all risk assessment. If you think saving a few dollars is worth the risk then you do you, but what I found when I put 87 in was it knocked quite a bit and reduced my FE by 1-2mpg which negates the price difference between 87 and 91+ over the course of a tank anyways. I'm sure some engines might tolerate 87 better than others, but for an overall fleet average most everyone will exhibit the same results with a few outliers that might tolerate lower octane better.
I would feel like it's safe to say, if you are in a pinch and you cannot get 91+ you'd be safe to run 87 until you can get to 91+.
Is that an accurate assumption?

Long term, your assessment of this seems very logical and makes perfect sense to me.
 
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I would feel like it's safe to say, if you are in a pinch and you cannot get 91+ you'd be safe to run 87 until you can get to 91+.
Is that an accurate assumption?

Long term, your assessment of this seems very logical and makes perfect sense to me.
Either one is "safe" as in you are not likely to permanently fail anything, but prolonged exposure to increased knock events especially during hot/high load events is what you want to stay away from. Even if you used 87 daily and then used 91 for long trips loaded down you'd be fine. The difference is 87 will, on average, not achieve peak fuel economy and have increased knock events. I've tested many vehicles in the desert up to boiling the coolant while hitting high knock events that sound like firecrackers in the engine bay and the engines still truck on. The problem is you can never predict when that 1 event will leave you stranded. The way I recommend is use case: If you want it to last, not have to worry, and get best fuel economy stick premium in, if you're leasing it and don't intend to keep it long term then do whatever fits the bill. If you are a long term user and you have to put 87 in just drive easy and you'll be fine. If you are in a high load situation I'd always keep premium in.
 

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