Premium Gas?

[intensebluert]

IMO, higher octane gasoline will improve performance because the Tundra's computer will advance the ignition timing with it. The reason these trucks won't experience pinging with 87-octane is because of the knock sensor/computer. Not saying that 87 will create ping but just because you get none on 87 doesn't mean performance will not increase with higher octane gasoline. Also STP fuel treatment in a tank of 87 octane gasoline does not equal 91/93 octane fuel. Premium gas will also increase fuel economy, whether it be the fact that it burns slower or not, it does work.

[SybErkRimInAL]

This is the first vehicle i've ever put premium in on purpose. I did it once in my old SUV on accident.

[Mark-5.7]

I'm going to try premium to see if there is any performance diff. Just because you don't hear pinging or knock doesn't mean anything because the knock sensors hear it first and retard the timing, therefore reducing power.

[Wallygator]

Toyotas are sensitive to Octane rating. I've tested it on the past five Toyotas I've had and I've already tested it on this truck. Mileage and overall driveability improve with Premium gas on my Toyota vehicles. YMMV.

[Fatty]

Has anyone of legitimate credibility verified that the toyota ECU actually alters the tune to suit the gasoline (octane rating)?

If so, it'd be the first I've ever heard of doing so. That'd be a pretty advanced ECU. The only way the engine could do so would be to advance the timing up to and just to the edge of engine knock.

Running higher octane fuel would in theory result in more power if like stated before, the ECU could run more advanced timing and/or lean out the fuel a little more to make more power.

I highly doubt that the ECU has this capability. Again, without a wideband input, the only way it COULD do so is to advance the timing such that it was just at the point of activating the knock sensor.....and I highly doubt that Toyota would do such a thing as it would be only a matter of time before you had a bad fuel/air/spark exchange and had damage to internals.

In some engines, namely high compression, high performance types, running higher octane fuel actually yields more power because the engine runs smoother. (with no change to the tune).

But for the most part, running higher octane fuel is nothing more than added insurance against engine knock...especially in hot Summer months where towing uphill in 100*F heat would DEFINITELY benefit from running 93+ octane.

I can tell you that the amount of any increase in fuel mileage you experience will NOT be equal to the cost increase of the premium fuel.

[Wallygator]

Originally Posted by Fatty

In some engines, namely high compression, high performance types, running higher octane fuel actually yields more power because the engine runs smoother. (with no change to the tune).

But for the most part, running higher octane fuel is nothing more than added insurance against engine knock...especially in hot Summer months where towing uphill in 100*F heat would DEFINITELY benefit from running 93+ octane.

I can tell you that the amount of any increase in fuel mileage you experience will NOT be equal to the cost increase of the premium fuel.

No clue about the ECU but my truck runs better and gets better gas mileage on premium. It only costs me about $4 more a tank to fill with premium. Even if I get 1 mpg better mileage it works out to about the same price for gas. This is a very simple way to figure it out but we'll see.

87 octane- $3.00 93 octane- $3.20 to $3.30 (comes out to $4 more a tank (20 gallons) at $3.20 a gallon)

If I use 20 gallons and I get 300 miles out of those 20 gallons, with 87 octane it costs me $0.20 a gallon. Now if I get 1 mpg better with premium (which I get 1-2 better) that would mean I would get 20 more miles out of 20 gallons of gas or 320 miles. So it would cost me $0.20 a gallon or the same as using 87 octane. So it costs roughly the same as using the cheap gas and the truck runs better so use what you want, I use premium.

I know that is not real world but it was the simplest way to explain it. Oh and I hope my math is right, it's late.

[Mickey]

Originally Posted by Fatty

Has anyone of legitimate credibility verified that the toyota ECU actually alters the tune to suit the gasoline (octane rating)?

If so, it'd be the first I've ever heard of doing so. That'd be a pretty advanced ECU. The only way the engine could do so would be to advance the timing up to and just to the edge of engine knock.

Running higher octane fuel would in theory result in more power if like stated before, the ECU could run more advanced timing and/or lean out the fuel a little more to make more power.

I highly doubt that the ECU has this capability. Again, without a wideband input, the only way it COULD do so is to advance the timing such that it was just at the point of activating the knock sensor.....and I highly doubt that Toyota would do such a thing as it would be only a matter of time before you had a bad fuel/air/spark exchange and had damage to internals.

In some engines, namely high compression, high performance types, running higher octane fuel actually yields more power because the engine runs smoother. (with no change to the tune).

But for the most part, running higher octane fuel is nothing more than added insurance against engine knock...especially in hot Summer months where towing uphill in 100*F heat would DEFINITELY benefit from running 93+ octane.

I can tell you that the amount of any increase in fuel mileage you experience will NOT be equal to the cost increase of the premium fuel.

Agree!

[Mickey]

Has anyone been to or seen where they distribute the gas to these tanker trucks? Reason being I watched for awhile not thinking much about it at the time to my amazement at a Hess distributor seeing Pilot J, Raceway, Shell, Chevron, Flash Foods (Exxon), BP trucks all there getting the same fuel. Who is the superior brand?

[guapo]

Mickey,

From what I have been told is all the tankers get their gas from the same distrbution center. But the trucks already have the additives in the tanks when they get the fuel load or they have to add it before getting to the gas gas staions. Since the load is so large I beleive that the additives are in before hand. We have a distrbution center down near the water and all the trucks get their load there.

[intensebluert]

Originally Posted by Fatty

Has anyone of legitimate credibility verified that the toyota ECU actually alters the tune to suit the gasoline (octane rating)?

If so, it'd be the first I've ever heard of doing so. That'd be a pretty advanced ECU. The only way the engine could do so would be to advance the timing up to and just to the edge of engine knock.

Running higher octane fuel would in theory result in more power if like stated before, the ECU could run more advanced timing and/or lean out the fuel a little more to make more power.

I highly doubt that the ECU has this capability. Again, without a wideband input, the only way it COULD do so is to advance the timing such that it was just at the point of activating the knock sensor.....and I highly doubt that Toyota would do such a thing as it would be only a matter of time before you had a bad fuel/air/spark exchange and had damage to internals.

In some engines, namely high compression, high performance types, running higher octane fuel actually yields more power because the engine runs smoother. (with no change to the tune).

But for the most part, running higher octane fuel is nothing more than added insurance against engine knock...especially in hot Summer months where towing uphill in 100*F heat would DEFINITELY benefit from running 93+ octane.

I can tell you that the amount of any increase in fuel mileage you experience will NOT be equal to the cost increase of the premium fuel.

I would hope it would. Most 0BD2 vehicles will. I believe these are OBD2.5 ECUs. Premium fuel burns slower creating a righer a/f ratio. The computer can sense these by the 02 sensors. The computer will compensate for it by either leaning the fuel input or advancing the timing curves. The computer also does this with the mass airflow sensor and it's determined by the amount, temperature, and density of the air coming in. OBD computers do not have one preset timing/fuel map. It has many and to has an advance/retard feature up to a certain point that is determined whether or not to be put into effect by the engine's sensors.

[1sicktundra]

no difference in the mileage for me

[Mickey]

Wallygator I will try it. Wednesday I'll make another 400 mile trip and we will see. I did 80mph and had 17.3mpg using the cheap stuff. I made 400 miles on a tank so we will try this tomorrow with a full tank of premium.

[Wallygator]

Yeah I'm interested to know if you feel a difference. I feel a difference but it could all be in my head. Even if my mileage didn't improve, four dollars is worth it to me because I think the truck runs better. YMMV.

[Mickey]

Originally Posted by Wallygator

Yeah I'm interested to know if you feel a difference. I feel a difference but it could all be in my head. Even if my mileage didn't improve, four dollars is worth it to me because I think the truck runs better. YMMV.

I have to go back down again for another week so I will try it again. Going down I didn't do 80. I did 70 and the mpg was only .1 better but I didn't have a complete tank of premium. Coming back I couldn't count because of the rain and wind gusts over 25mph. When I go back down tomorrow I will try it again.

[polcat]

My job in the military is Fuels. In my job we have to sample and Lab test different grades of fuel from Jet fuel to diesel to mogas (or unleaded fuel) to make sure they pass certain standards. The truth is that the different grades of unleaded gasoline have different "Flash points". This is the difference that your engine sees. When your engine flashes at different temperatures it directly effects the timing of the engine. Although this is so minute by scale, over time your engines ECU learns through sensors, the time at which you cylinder flashes, in turn adjusting the other components accordingly. Higher octane gas burns hotter and faster, which creates more power and a cleaner burn.
Bottom line is there are differences in Octane and the higher the octane (within limits to your ECU tune) the easier and better your engine will run
The good things about todays cars/trucks are the ECU's are better tuned for todays crappy gas. You will see suddle differences between grades, but they are there. Hope that helps a little.

Just be glad you dont have to use Bio-diesel. That crap sucks!!!