I have a 98 12 valve. I love all the information on this website but unfortunately I don't understand a majority of it. Is there such a book as Cummins for Dummies? Or what would manual is out there that I can start reading to get a better idea of what I have?

 

could always get an engine manual from cummins as a starting point.

 

Your 1998 12v Cummins is considered the best of any year for fuel economy!

Dave Fritz of Virginia Tech
has put together a great web page of Ram information
mostly about the Cummins.
Try to read everything there
and start at this page:

http://dodgeram.org/tech/dsl/FAQ/diesel_faq.htm