Smeltdown doesn't talk much. Generally, he lets the furnace in his chest and the flame-spewing nozzles he has in place of hands do the talking.
Marvel comic continuity
Smeltdown was part of a marauding group of mutants who encountered the young Autobots Tailgate, Flattop and Subsea in the Underworld when the trio foolishly decided to take the ancient Autobot "trial by fire". Smeltdown slew Flattop, and subsequently died in a spectacular explosion when Tailgate ruptured the gas tank in his furnace, taking Jackhammer, Slayride, and Warhead with him. The flames caused by his fiery death soon served as a funeral pyre for Rotgut , and the explosion ruptured the barrier between the Underworld and the lower levels of Cybertron, allowing the demons to escape.