Rust on tail pipe
I assume you mean on the inside of the tailpipe? If so, it's normal and not a problem. The moisture that caused the rust is a result of the catalyst process in the converter and has nothing to do with the engine.
It also means you probably do alot of short hop driving. The system is not reaching a temp to evaporate it before it runs out which you can sometimes see happen from some cars. Moisture is naturally part of the combustion process, but after the catalytic converter the system is considerably cooler. one of the few benefits of burning oil is that the inside of the pipe gets a sooty coating that sort of protects the pipe. The rust on the outside bottom of the pipe is from water dripping off and not from an engine process. Perfectly normal.






