87-89-93 octane?

[tommlev]

Being new to the Subaru family, I am wondering does 89 or 93 octane make a difference in either the 3.6l or 2.5l engines? I tried that in my Jeep Grand Cherokee and my wife's Caravan before we traded them in and it made no difference at all. I tried the 89 octane in the Tribeca on the last fill up and got about 2mpg better but had more highway driving on that tank.

[BzB]

wondered the same so i tested it out.. i tried 89 for a few weeks and then switched to 87 for a few weeks. didn't notice a difference in mileage or power. had a few extra $$ in my wallet though! :)

[SubieDriver]

On the '06/'07 Tribeca with the 3.0, 91 octane is specified, but the '08+ with the 3.6 liter has lower compression ratio, so lower octane is required. There is no benefit to running 91 or 93 octane in the 3.6 except maybe the additional detergents included in premium fuels. Run a little now and then to keep the engine clean, but you'll get no performance benefit.

[Magic Marker]

Just enjoy being able to run 87.......

[tommlev]

Thanks for the help. Just wanted to see if there was any benefit to it in the Subaru's.