long story short i have had my Maxima for 9 months a month later after i bought it i started hearing this knocking sound kinda like a rod bearing starting to go out but didn't really worry bout it since i have an extra engine so i decided to just leave it like that. well my car hasn't really been runing to good lately and yesterday i got the batt light on. so i got my multimeter out and checked it and it was only pushing like 12.2 v on or off, so i bought an alternator today and replaced it and all i have to say is i love my Maxima my engine is so smooth, strong and quiet no more knocking what so ever. it feels like a new engine i never thought the alternator could be bad for that long. also i want to say thanks to everybody on maxima.org for the help i got on search and stickies for the alternator replacement took me like 1 1/2 hours( damn long bottom bolt)

 

when I bought my I30 a couple years back, it couldn't make it out of the driveway without dying. Put in a new battery and it ran perfect.