The "No-Buy" List: Which diesel years are the biggest money pits?

[AxleExpert]

Everyone knows about the 6.0L and 6.4L Ford issues, but what about the less-talked-about years? Like the early LML Duramax fuel systems or the first-gen Aisin transmissions in the Rams? If you had $30k to buy a used diesel today, which specific year/model would you RUN away from regardless of the price?