Each truck has it's issues.  I am a Dodge person and I will try to give you an honest opinion.  The Fords that were built from 03' to 06' have the 6.0 diesel in them.  No way is it any comparison to the 7.3 that they had earlier.  The 6.0 has been and still is plagued with issues.  The Dodge isn't without issues but has none with the engine.  The new 48re automatic is a great improvement over the older trannies with very few issues. The 06' auto trucks can be equiped with an exhaust brake that is approved and can be installed at any dealer.  The manual tranny trucks can have an exhaust brake on any year and it is also approved.  The Cummins is a heck of a motor.  You may have issues with the A/C or balljoints on a Dodge. That's about it.  Go drive them both and see which one you like. You can research the Dodge at www.dieseltruckresource.com. I don't know a Ford forum you can use.  Maybe a ford owner can pipe up for that.