You really have to find and use a LBS that you can trust, try and get acquainted with the mechanic and ask to to speak to him directly, helps to at least know the theory so you can at least, as I routinely do ask how much longer you might get from a part and what might happen if you push it too far
If you're desperate for cash, ahem, you can push parts a surprisingly long way, the only exception to that would be brake pads, when metal touches metals you really have to stop right there
If you're desperate for cash, ahem, you can push parts a surprisingly long way, the only exception to that would be brake pads, when metal touches metals you really have to stop right there