At least Jeff Porcaro, David Paich and Lukather played and wrote on a ton of sessions of the time. In my mind, they're definitely a key ingredient in the 80's "L.A. sound" I love so much. They (well, at least Jeff Porcaro) also recorded lots in Japan for Japanese AOR artists, produced by guys like David Foster and Jay Graydon!
I wouldn't say that they were a "wrecking crew" in that same sense, it was more like they were hired guns by the top honchos like Foster, Graydon, Quincy, Arif Martin etc. Also, they didn't do the sessions as a "band".
Check out Jeff's sessionography and start hunting! Anything with a Porcaro drum track is worth your while Link