Depending upon the geographic location of your vehicle, exhaust systems may or may not need frequent attention. Typically, the exhaust system in a car does not need much attention until higher mileage or advanced years. Most cars do not need any exhaust work for upwards of 8–10 years due to the corrosion resistant, stainless steel used in exhaust systems installed in the factory. However, repairs will become more common and more expensive as components age and develop holes and leaks or when they fail completely.
A louder sounding exhaust is the easiest symptom to identify, and a technician can easily point out where the leak exists when the car is on a lift. The prime culprits for leaking are the flexible weave near the front of the exhaust, and the union where two flanges are bolted together. The flexible weave allows for the exhaust system to move around when the car twists and turns. It is the weakest part of the exhaust in terms of thickness and it takes the most abuse. The flanges are made from anodized aluminum, which does not resist rust and oxidation as well as stainless steel, so they begin to rust sooner. Where these flanges meet is also a spot that tends to collect moisture. Sometimes, the system can be repaired with some new flanges and a new gasket to seal them. As the system ages and develops holes or more significant leaks, welding may be an option to repair through either patching a hole or cutting out rot and fitting in a new piece and welding the gap. At some point the system will need replacement in larger pieces.