How many use premium fuel and why?

[FJ40INTOW]

How many use Premium Fuel?

I use premium for one because it is recommended.

I tried using Regular unleaded and my MPG went down and it did not run as smooth.
I typically average 23 mpg mixed during the week with most of time commuting.
The truck also runs very well and I can't ever tell it is in V4 mode and is seamless switching modes.
I do have the 6.2 with 8 speed.

 

[Naz 23 Esky]

How many use Premium Fuel?

I use premium for one because it is recommended.

I tried using Regular unleaded and my MPG went down and it did not run as smooth.
I typically average 23 mpg mixed during the week with most of time commuting.
The truck also runs very well and I can't ever tell it is in V4 mode and is seamless switching modes.
I do have the 6.2 with 8 speed.

For the lifetime of my 11 denali I only used premium and engine was solid when traded with 132000kms . Figured when you're dropping $80k on an SUV only makes sense to put what they recommend even if that means dishing out for premium. Only time I would use regular was when we did road trips from Toronto to Miami or anything longer than 11 hours. Mind you my new 16 SLT I ordered last year has been using regular and the cheaper gas is a nice plus.

 

[Kpwweb]

Some premium here is ethanol free. DI engines seem to run better with ethanol-free gas.

 

[swathdiver]

All engines run better without ethanol.

I learned thirty plus years ago to run the top tier high octane fuels. No matter the car, they always get better mileage and run smoother, cooler and make more power.

Until recently, the price difference between regular unleaded (87) and premium unleaded (93) was usually within 20-25 cents per gallon. It made no financial sense at all then to run the cheap gas because one used more of it compared with the higher octane rating.

Now, today for example, consider this.

Let's say you fill up your truck with 24 gallons of 87 octane at today's average price of $2.39 a gallon, that's $54.96 for those of you in Rio Linda. At 16 miles per gallon fuel burn (you'll have to work out your own numbers here) you can travel 384 miles on that tank of gas. That's .143 cents per mile.

Now compare that with filling up your truck with 24 gallons of 93 octane at today's average price of $2.839 a gallon, that's $68.14. At 18 miles per gallon fuel burn you can travel 432 miles on those 24 gallons, .158 cents per gallon.

So, as for me and my house, do I think paying an extra .015 cents a mile (premium over regular) is worth the better quality fuel and all of its benefits? That .015 is a tenth and a half of a penny per mile folks. You betcha!

 

[cardude2000]

If the manuf. calls for high octane, use high octane. And yes, I use it in my denali 100% of the time. That said, much of the stuff out there about octane is old wives tales/myths. Here's a good mythbusting article:

"Contrary to popular belief, high-octane fuel will not make your car more powerful, improve your gas mileage or make your engine run cooler or hotter, said Doug Wilmot, an engine performance development engineer at Chrysler Corp."

http://articles.chicagotribune.com/...190257_1_octane-premium-gasoline-premium-fuel

 

[swathdiver]

"Contrary to popular belief, high-octane fuel will not make your car more powerful, improve your gas mileage or make your engine run cooler or hotter, said Doug Wilmot, an engine performance development engineer at Chrysler Corp."

Mine own experience with Buicks, Oldsmobiles, Cadillacs, Kias, Hyundais, Fords and GMCs says otherwise.

Ever run Sunoco 104 unleaded in a car? I have. Car's engine temp dropped 6 degrees, picked up .2 and 2mph in the 1/4 mile, ran quieter at idle, awesome stuff. I know it picked up MPG but most of that week was spent driving a 1/4 mile at a time at full throttle!

One of my racing buddies used to make his own race fuels but I was content to drop in a bottle of 104 Octane Booster from the shelves of Discount Auto or Walmart with every 1/2 tank of gas if I didn't want any knocking when running 18 pounds of boost on pump gas.

 

[iamdub]

There are far too many variables between vehicle brands and generations to make such a general statement that premium fuel is/isn't better than regular. For one, "premium" is a sales term. It's to make you feel like you're part of an elite class of people putting some super special fuel in your tank that's only attainable by those in your "class" willing to pay for it. It's the same fuel as mid- and regular grade except with a higher octane rating. Yes, some makers include other additives and detergents in their high-octane fuel that they don't include in their lower octane grades. But, as for the fuel itself- what your engine is igniting to convert chemical energy into mechanical energy, that part is still the same. If your engine runs better with higher octane fuel, then it's because it's set up to do so.

I agree that engines run better/more efficient on 100% gasoline versus x% ethanol. Ethanol has a higher octane rating, so that would make the fuel less volatile. Less "bang" per unit of fuel means that the engine will need more volume of fuel to perform the same amount of work as if it had a lower octane (more "bang") fuel. Then there's the whole hygroscopic issue with alcohol fuels...

My Tahoe is spec'ed to run regualar 87 octane fuel with 0% to 85% of ethanol. I notice detonation and reduced power and fuel economy when running 87. It gets better with non-ethanol 87, but still detonates some. I don't notice any detonation with mid- and high-octane grades, ethanol or not. Maybe it's the quality of fuels in my area or carbon buildup on the pistons raising the compression and/or creating hot spots that causes the spark knocking on 87. I run 89 or higher when I drive because it's guaranteed to see WOT at least a few times. Jenn drives like a grandma so the cat piss is fine for her.

 

[swathdiver]

There are far too many variables between vehicle brands and generations to make such a general statement that premium fuel is/isn't better than regular.

Well Dub, that was the point of my post. It's something I've been paying attention to for thirty years. The cars have changed, the fuel has changed and yet it still pays to run the good stuff.

 

[01SLE]

There's absolutely no reason to run high octane fuels in these vehicles daily.

Swathdiver did the math for you right there, it costs .015 cents a mile more to run "premium" fuel. But the end of your statement is false: there are no added benifits of running higher octane fuel (generally - see comments about additives). The only benifit is the increased resistance to detonation allowing the engine to run more advanced timing and/ or a leaner air fuel mixture netting you better gas millage and potentially a high max power output. But the increase mpg doesn't out way the increased cost at the pump, at least by his math. And the increase in power output is most likely marginal.

The engine management systems and advanced sensors in these vehicles (and most vehicles made since 1996) allow you to run lower octane fuel safely. The first sign of a knock count cause the EMS to retard timing slightly or switch fuel maps resulting in a slightly less efficient combustion but eliminates predetonation. So driving around with 87 octane fuel in the tank doesn't mean you're vehicle is experiencing a knock count. If you feel less output, it's retarded timing or a richer air/fuel mixture. You aren't "feeling" predetonation on a new vehicle like these because it will be corrected almost instantly by the EMS. If the knock count is prolonged and the EMS can't eliminate it with adjustments you have bad fuel or mechanical/ electrical problems and you'll see a check engine light and code for excessive knock counts.

These vehicles aren't pre OBD muscle cars where you feel and hear knock/ping.

 

[Rdr854]

The recommendation in the owners manual is 87 octane or higher. Thus, the motors are designed for 87 octane.