91 MAXIMA shift problems

Hi, My 91 maxima shifts slow, bangs into gear and is using a lot of gas. It did this last month, then was fine. last week the alt light came on and since then its back to shifting bad. Tha charging system checked out ok and the light is now off but its still bad.... any ideas? it has a new battery and spark plugs.

...so many ideas that I filled a wbsite with 'em. Theres hope.

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