While increasing octane will not help, choosing a good brand of gasoline does. I do like Chevron gas, though I think that most of the large name companies are just fine. Out of personal preference, I won't put Citgo gas from 7-eleven in any of my cars.

Didn't I just read that they are finally doing away with the oxygenated gas?

As far a shaking - the first thing you should always do is have your tires balanced. It's cheap and very often does the trick.

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"If you hit them hard enough, anyone will put the ball on the ground." - Bronco Mendenhall