it is cat back. youtube search "alero exhaust" for sound clips . it is 2.5 kit it is lower then the stock exhaust. yes 88-1474 is the right kit this is where I got the kit
Performancecenter.com
1731 Kaiser
Irvine, CA 92614
Phone: 800-719-8100
Fax: 949-598-8294
this is who I got my cat from it is for the 3.4
info@rsautoparts.com
here is the email I got about the part number :
I just wanted to give you a heads up that MAG23435 for the Alero has been superseded by MAG23520. It's listed for the Malibu 3.1L, but is for the 3.4L as well. I just wanted to let you know so you didn't freak when you saw the part number on the box.