I'm pretty sure he dubbed the roars for the hulk creatures, but he also did Godzilla roars in the Hanna-Barbera episodes back in the 70's. Between The Incredible Hulk and Godzilla, I like Godzilla the best.

I thought about running an ad that says no to spend lots of money on gym memberships and nutritional diets and to send me five dollars, and I would teach people how to beat Lou Ferrigno up. My mom and brother said it's a scam and that I could get in trouble for it though; but if anyone wants to know, all you have to do is ask.
Take care and God bless