We’ve all heard a car or truck thunder by that needs a new muffler, but there’s actually more to the exhaust system than just the muffler. The exhaust system has three main functions. First, it safely gets the hot exhaust gas from the engine, out through the tailpipe. Second, it treats the exhaust to remove harmful pollutants, and third, it muffles the engine noise What is meant by the fact that it safely moves the exhaust? Exhaust gas is poisonous.