Even though Nissan isn't listed as an automaker recomending "Top Tier" gas. I found this subject kind of interesting anyway.
There seems to be arguments on both sides on whether this is really that big of a deal?

http://www.toptiergas.com/index.html#

 

It doesn't help that all types of gasoline have at least 10% ethanol, at least in Texas. Less efficient and less clean burning than what many believe.

 

If you want to see the difference between gas grades, regular or premium and which brands are better, get a lawn or snow blower or and small engine yard machine/tool and fill it up with premium, then use regular, the smoothness and vibration of the engine will shock and shake you, and certain regulars will feel as smooth as premium and some will beat the hell out of you.

Everything I have heard and read about gas means nothing until you strap a backpack leaf blower on, filled with regular and turn it on, 20 minutes into blowing leaves you feel like a jack hammer is destroying you, then filled with premium its feels like your sitting in an electric massage chair, the difference is night and day, think about the extra stress your engine is taking on

 

Chevron uses a very good amount of detergent additives. I've always used Chevron on my 4th gen. Last time I checked my intake valves (not long ago), they looked sparkling clean. By the way, I don't dump fuel additives in my fuel system.

 

Good feedback. I agree with not using the fuel additives, outside of the occasional fuel injector clean-out.

 

I stick to top tier brands (Chevron, BP, Shell are my brands) because I run 89 (midgrade) octane. I have owned nothing but Maximas since Oct of 1984, and after the first 18 months, I have switched to a top tier midgrade with every one of my Maximas, and they all ran beautifully on top tier midgrade gas. I was never able to detect the faintest hint of change in performance or MPH.

On those very rare occasions where I was 'boondocking' it (middle of nowhere), and had to buy an off-brand gas, I took only their premium. Even with top tier brands, I never use regular, because that is just too far from the fuel this car is intended to run on.

 

Same situation here Light. I use Fred Meyer which is Shell Gas?

I shouldn't expect too many responses to my question when inquiring about gasoline cleansing agents. Seems most major dealers are providing what is required?