My largest car maintenance cost is exhaust pipes, mostly catalytic converters. I do not think this is the case for most people. What am I doing wrong?
I tend to buy cheap cars (<£500), change the oil myself, get the brakes changed when they squeak and change the car if there are any repairs that cost more than the car. I do not drive slowly, such that I am not surprised that I get through tires and brakes a little quicker than other people. However by far my largest maintenance cost is exhaust pipes (mainly catalytic converters).
It is always the connecting pipes that corrode and/or break, rather than the actual catalytic element. I do not see an obvious link between driving style and exhaust pipe corrosion, and I am not aware of any preventative maintenance that could affect the exhaust pipe. On one occasion I went through three in the course of 4 years on the same car, and in two of those cases there was very little corrosion, the pipe sheared above the catalytic converter. I live in the UK, but not near the sea.
Is there something I can do to make my exhaust pipes last longer?