SilverLady

G Man - I did only one tank of 87 (actually higher, as I mixed about 3/4 tank with the 1/4 tank of Premium 93 in there). I really felt the GX became sluggish and stayed that way.

I've since filled up with premium 93 a couple of times, and I think things are back to normal. (I don't think I have ever seen the recommended 91 around here).

Price today was $3.01 for Premium 93, $2.99 for middle 89, and $2.87 for regular 87. With that kind of difference, taking tiniest hit in milage or performance makes no sense. There was sometimes a 20 cent difference back when gas was $1.20 a gallon!

I wish the GX had a bigger tank. I'm thinking of asking one of my friends to teach me Hindi so I can talk to the gas station attendent during my frequent visits!

sayadil

hey guys

well i have been using 89 ever since i bought this vehicle... i did replace it with 91 n 93 few times but dint really notice that much difference. putting 89 does make the gx seem sluggish... so i stuck with 89. I get 375 miles per tank till the yellow light comes up. fairly good from a V8
I do add STP Gas treatment (red bottle) once every few months

The G Man

It seems like there is no 91 octane here in the northeast, might be a regional thing. As far as the difference between 87 and 89 octane, below is something interesting I read on another forum:

My gov't agency is responsible for testing octane and fuel quality within our jurisdiction according to ASTM standards, and I will tell you that the tested driveability index between the super and regular grades is miniscule. Another thing I must tell you is that if you have a vehicle that is designed to run on 89 octane midgrade product, don't buy 89 - switch back and forth between 93 and 87 at a 2:1 ratio (87 to 93). The reason being is that the 87 consistently tests at 87.5 - 88.0 octane, whereas the 89 tests closer to the actual 89.0. It's not worth the difference in price from 87 to 89 when they are so close in actual octane numbers.

ADVocate

I agree with Adil, you don't need premium. I have been using the lesser grade for a while. I started out with Premium, as I had with RR's I have owned. But, they NEEDED the premium. The engine on the GX is designed to be more flexible. The drop in "crispness" was marginal, and in my POV does not warrant the $.20/gal differential between the grades in my area. If anyone is so anxious to seperate themselves from their money, perhaps you can try the stock market. At least you might get a return periodically. There must be some aristocratic distinction between using the two grades, for it to be pursued so emphatically, which eludes me. My loss I guess ... or is that my gain?

The G Man

Alright, you talk me into it, I will try a tank of 89 octane next.