From what I've read, the 3400 is kinda prone to leaky lower intake manifold gaskets. One sign is wetness of the hood liner above the belt path. My wife'* 04 has started doing it recently, and with 35k on the odo, it'* going in soon for some warranty work.
my alero is basically the grand am but a little more refined the 3400 is really powerful in these cars and throws you into the seat when punched. watch the lim gaskets tho they are a serious issue with the 3400 and if left alone you will be shopping for a new engine for your new car