I remember seeing somewhere complete cummins engines for $7k and theres a local shop that will rebuild the engine and put in a dual turbo setup for $7500.

Theres a company I ran into on Ebay that sells Cummins engines from 12v's to CR's, and from long blocks to complete drop in engines. Even the drop in engines were well under $10k.

my cousin took his truck in to the dealership for oil change and service, they called him up saying his rearend is shot needs a new one.cause it has 130,000 on it.they just trying make money thats it.

Those service advisers are paid commission based on sales volume. They also have quotas. It is sad but that is the way their system works and that is the way they are taught to deal with customers.