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What kind of gas are you putting in your XC90? Dealer filled up with Premium but said I could do okay with 91 or even 87.

Thoughts?
 

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You will need to use 91 or higher, with this engine.
 

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Wait I thought we can use 87, but the recommended fuel is 91+ if you wanna get more out of the engine (efficiency, power, etc)?
Yes, of course. My expression "you will need" was geared toward getting the performance and fuel efficiency that one expects to get when he/she buys this car. In order to do that, he/she will need to use gasoline that is has at least 91 octanes.
 

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Premium. I've always filled a vehicle with what was recommended by the manufacturer. And with premium not being $5+ a gallon as it used to be I'm not complaining.
 

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People buy expensive cars and cheap out on gas by few cents lol :facepalm:
 

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Yes, of course. My expression "you will need" was geared toward getting the performance and fuel efficiency that one expects to get when he/she buys this car. In order to do that, he/she will need to use gasoline that is has at least 91 octanes.
To echo Grecian, you should use 91. This is my 4th Volvo and I can assure you they do not run as well with ethanol or 89, less power, not very smooth, worse mileage. Boosted engines respond very well to octane.
 

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To echo Grecian, you should use 91. This is my 4th Volvo and I can assure you they do not run as well with ethanol or 89, less power, not very smooth, worse mileage. Boosted engines respond very well to octane.
Yeah. Seems obvious I'd think. What's the differential in cost?

About $0.20 per gallon? So about $4 per tank? If you fill up once per week that's approx. $200/year. For a $60+ thousand dollar automobile...

Just skip the 'premium' Starbucks and swap in the 'regular' Dunkin Donuts or McDonalds coffee instead and you'll end up sticking to the same weekly expenditure level!
 

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Oooooook. The compression ratio in this vehicle is 10.8:1.

Ten point eight to one. Ten point eight to freaking one. That is HIGH. Very high. My Porsche Macan S with a twin turbo engine has a 9.8:1 compression ratio.

If you're going to exercise your right to play stupid and be cheap, this is not the vehicle to do it in.

If you are using anything under 91 octane (and if you look at charts, it seems as though many will indicate anything below 93 octane), you are going to get detonation which causes your knock sensors to retard the ignition timing properly so that you aren't burning excess fuel, overheating the engine or giving off higher emissions. So what you are doing is relying on your knock sensors to protect your engine and, even if the knock sensors work properly, the engine is not being allowed to run as designed. All of this being said, not all engines are created equally as they are not all designed the same, so one engine with a 10:1 compression ratio might operate optimally with one octane while a different engine with 10:1 compression ratio might operate optimally with a different octane.

The point is, Volvo is recommending an octane rating for a reason, and it is NOT to give the perception of "luxury" by demanding "premium fuel".
 

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Very, very few people understand what Octane level is and how it relates to performance engines. Put very simply, octane is the amount of compression the fuel can take before ignition.

If the engine doesn't need a higher Octane, you're throwing money away. However, with a turbocharged, supercharged engine, it's certainly more necessary than in most all other situations.
 

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My dealer filled with 87 upon delivery. I immediately noticed a difference driving versus my earlier test drives. At 1/2 tank I topped off with 93 and immediately noticed a difference in throttle response.
 

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This is great info, hopefully those planning on using 87 octane will reconsider!
 

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I found it interesting and somewhat disturbing that when I first test drove the XC90 the salesman was touting one of the great selling features of the car was that it only required 87 octane gas. They need to stop that sales pitch.
 

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To be fair, in NY we get fleeced for premium. In some cases it is 50 cents more than 87....plus we don't have many stations that sell 91....so you have to go all the way up to 93. Even for those of us able to afford this vehicle, it is a steep premium in gas prices. I really hope it does improve gas mileage and therefore help pay for itself, but we shall see.
 

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I really hope it does improve gas mileage and therefore help pay for itself, but we shall see.
Well, keep hoping.
Ever heard the saying "Correlation does not imply causation" before?

The only way higher octane fuel can lead to improved MPG is if you're engine is running so poorly on lower Octane gas that your MPG is lower than it should be...
There's roughly a $.40 spread from 87 to 93 here in Texas - so you're not getting as "fleeced" as you may think..
 

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In our old xc, when you put 87 in, the mpg tanked. If you put 91 in you would get about 50 more miles per tank, which if you did the math from the cost difference from 87-91, 91 oct comes out cheaper per tank/mileage.

i suspect the dealer put 87 in our new xc also, caus ewe filled up the tank and the car drives night and day, and the mileage also has improved.
 

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People buy expensive cars and cheap out on gas by few cents lol :facepalm:
Hahaha! I don't think XC90 owners here uses 87 octane. Just stating the fact that the car can "in case of emergency" can go as low as 87 for its fuel.

As for the dealer who filled the car with a lower octane fuel, that's what you call cheap! :D
 

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Hahaha! I don't think XC90 owners here uses 87 octane. Just stating the fact that the car can "in case of emergency" can go as low as 87 for its fuel.

As for the dealer who filled the car with a lower octane fuel, that's what you call cheap! :D
True and yes very cheap dealer lol I've been filling up my X5 with 91 octane since the beginning :D So will be nothing new with our T8 lol
 
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