What grade gas?
 

My salesman recommended mid-grade (87 octane) for my 2014 A6, stating that that grade is preferred for those of us in a higher altitude.

Can anyone confirm this?

In my 2004 Altima I've primarily used 91 with the occasional fill up being 87 depending on where I am and pricing. The Altima still runs like a stud w 147k miles on it.

Thoughts?

This saleman has no idea. Even manual says 91+. I run 93 shell only.

Never trust a salesman. Never.

If your midgrade is 87 what is your high test?

In Florida it is mostly 87-89-93.

I have seen them sell lower octane gas at high altitude places like Colorado. I think it goes 85 regular, 87 mid-grade, 91 premium, right?

The theory is the lower air pressure at higher altitudes reduces the risk of the engine knocking so you can get away with using lower octane gas. However, both 2.0L 4 cyl and 3.0L V6 A6 engines use turbo- or supercharging which compresses the air going into the engine above the outside atmospheric pressure. Thus the theory does not apply, and you should still use the manufacturer recommended 91 octane gas.

^^^^ This.

Thanks all for the feedback. I'll stick w/91. I typically pump at Sams Club Gas Station near my home and find the 91 octane price to be very similar/close to 87 mid grade price.

I only use premium Top Tier gas, by me I find Quik Trip to offer best price and is Top Tier. I actually use same station and virtually same pump 90% of the time.

I once had a salesman tell me if I purchased his car I would win the lottery and would stop losing my hair. Neither happened.
In the mountains or at sea level, it's Top Tier Premium 91 or 93 octane all the way, every day, no matter what a salesman may say. (When in doubt, read the manual. It recommends Premium and there's nothing in there about the lottery of hair loss.

Top Tier gas is just propaganda. Its bull****. As many of you know, and some may not since my thread was deleted, I've been working closely with DiabloSport for 7 years, and in that time I've logged countless cars. Many of the "Top Tier" gas has a tendency to knock, especially Shell, Chevron and 76. Don't base what you buy on propaganda, buy based on each particular manufacturer.

The best fuels are Exxon-Mobil, BP, and sometimes Sunoco (sometimes not. They have been known to water down their fuels on occasion, though thats more on a particular station or distillery than the company as a whole). Cleaners affect combustion, so stuff that has lots of cleaners will knock. Shell has lots of cleaners, so it should be avoided. Texaco isn't great either.

Well on a good note.. i just Googled the station I use most frequently and find that Sams Club sells Exxon gasoline. Not only is this station located nearby, the price for "Top Tier" is that of what i'd find for 87 mid-grade at non Sams club stations locally here in Aurora, CO.