Driving a vehicle with a broken or malfunctioning muffler or exhaust is dangerous. If you continue to ignore muffler damages, it leads to exhaust leakage, which is itself a safety threat. The leakage may introduce carbon monoxide to your cabin thus creating discomfort for you and the passengers. You need to consider repairs if the muffler is leaking, the exhaust system is producing bad odor, or you it is producing loud noise while driving the Hummer . Keep checking at the fuel average of your Hummer as well because fuel inefficiency also gives a clue about malfunctioning muffler and exhaust. When find any of the sign, you need to repair it at the earliest by our qualified and well-trained mechanics. Here are the signs that indicate your muffler needs repair or replacement.