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Must Porsche Cayenne SUV use premium gasoline at 5,200 ft?

Woman complains abouthe cost of premium gasoline and her gasoline consumption.
I suggested that she GENTLY accelerate, not “floor it” as it sounds that she does.
At Denver’s altitude, can she use regular?
Denver’s octane ratings are 85, 87, 89.
Thank you.

Woman complains about the cost of upkeep of the white elephant she bought and keeps in her backyard?

Seriously, if the car specifies premium, use it. Period. The car was designed, engineered, and built to use premium. It needs it. End of discussion. The price difference is negligible is she’s bother to do the math.

No Porsche was built with fuel economy in mind.

Absolutely use premium. The adjustment for altitude has already been done by the gas sellers, down 2 points from sea level gas.

SOMEBODY has to buy unleaded premium, otherwise they would stop selling it. Porsche owners are the PERFECT candidates to add to the oil companies profits…When the oil companies sell low-octane gas in high altitude areas, they never seem to lower the price to match the lower octane…More unearned profit!

Thank you.
What octane rating should our 2008 Expedition be using? I recall the owners manual stating 87 octane but now forget. We have been using 85.

At 5,200 feet, your friend may use 89 octane rather than the 91 required closer to sea level. In Denver, that would be premium. If your friend does not want to buy premium, she should not have bought a premium performance vehicle that requires it. Besides, the price difference is, what, $3-$4 a tank? I say trade it in for a Pontiac Vibe. They’re similar enough, right? And the Vibe will run on regular with no complaint.

Does this indicate the state of our economy? When the well-to-do are trying to save 20 cents on a gallon of gasoline while traveling 85 miles per hour?

If this is a turbocharged Cayenne the cylinder pressures will be as high if not greater than the non turbo Cayenne. At part throttle, (less than half throttle) the turbo can produce a positive pressure (boost).

If this is a non turbo and I were driving it I would use regular fuel but I know what detonation sounds like and I certainly wouldn’t drive on mountain grades with regular grade fuel.

Use premium gasoline.

High end car = high end running costs. It’s staggering how some people can shell out $60k+ for a high end car and then bitch about having to use premium fuel.

@Robert Gift

From page 364 of your owner’s manual

“Octane recommendations
Your vehicle is designed to use
“Regular” unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.”

An owners manual with over 365 pages?? I’ve never seen one of those…

“We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.”

My Crown Vic’s manual says the same thing but I feed it Denver’s 85 octane regular when we are there or traveling to get there. I’ve never detected any detonation or had any problems…

Robert Gift…at 5200 feet you can use 85 octane in place of 87. That is only if your Expedition actually recommends 87.

That owners manual may be way longer than 365 pages because I would think that a fuel recommendation would not be on page 364 near the end of the book.

Jeez, how many people are going to skim 20 pages much less a tome that required the slaughter of a small forest to produce. :slight_smile:

behold the 390 page 2008 Ford Expedition Owner’s Manual
motorcraftservice.com/?link=002&urlfile=/pubs/content/~WO8EXD/~MUS~LEN/41/08exdog1e.pdf

The MSRP of a 2012 Porsche Cayenne is $107,100. If you can afford to buy a $107,100 car, you should have the time to read a 365 page owner’s manual, along with the prospectuses for each of your retirement accounts.

Many owner’s manuals list vehicle specifications on the back page, and I hope that is what Porsche did.

As cars have become more complicated, their owners manuals have become thicker. It’s no longer sufficient to tell you how to use the seatbelts and how to put it in gear. Now they have to tell you how to pair your bluetooth phone to the car, and how to use the navigation system, and how to program the homelink garage door opener, etc etc etc. Cars are rolling command centers now.

85 octane in denver is equivalent to 87 at sea level as far as engine knock is concerned. available power will be less however.

They all look the same after they have gone through a shredder…The only real difference is the cost per mile to own and operate…

@Caddyman: Yes, they all look the same after the shredder, but the same could be said about people I suppose, and it doesn’t really say much about how they lived their lives… You can also eat nothing but vending machine sandwiches and they will probably keep you alive, but that’s about it.

I will probably never be able to afford a Cayenne, and it may not be my cup of tea either, but I truly despise driving econoboxes. Life is too short to suffer so much of it in cheap, lousy, unpleasant cars. To me, it’s well worth a little lousier gas mileage to have a car that’s comfy, spirited, and brings a smile to my face when I drive it.

That said, I really don’t understand the person that can afford to shell out so much for a really nice car and then cheaps out on a couple of bucks per fillup and likely on maintenance too.

“We do not recommend the use of gasolines labeled as “Regular”
that are sold with octane ratings of 86 or lower in high altitude areas.”

Thanks, FoDaddy.

Hate to do it but will change from using 85 Regular to 87 Mid-Grade.
How much more money will be spent with no.ticeable difference?
I’ll also figure outhe cents/octane between the different grades and watch the odometereadout feature which indicates miles/gallon.

I drive at lower speeds in a lane not impeding others, accelerate gently, coast, and use brakes as little as possible. But emergency transports completely ruin the fuel economy accomplished.

-Had no idea that her Cayenne SUV costs so much.-

The Cayenne Turbo starts at over $100k, the base model starts closer to $55k, and the S starts around $65k.

2008 Cayenne S. She thinks it requires Premium octane.
We have 89 and 91 “Premium”