This quest is not available in game.
Bring Gahz'rilla's Electrified Scale to Wizzle Brassbolts in the Shimmering Flats.
Deep in Zul'Farrak, the sand troll city in Tanaris, there is a sacred pool. From that pool the trolls summon a huge beast! Gahz'rilla! He's so fierce that even his scales crackle with energy. It's that energy I want to harness for my car!
Bring me the electrified scale of Gahz'rilla!
But the summoning of Gahz'rilla is a well-kept secret of the trolls. To face him, you must first wrest the secret from them.