The official US Gov doc:
https://www.justice.gov/opa/pr/department-justice-epa-settle-derive-systems-over-aftermarket-emissions-defeat-devices
It's getting worse an worse for tuning companies. :(
I use this one: https://www.amazon.com/gp/product/B00WPW6BAE/?tag=jhdiesel-20
However, I never used it on a EcoDiesel. CTS hooked up for that. It did work well on a Duramax for what it's worth. It will clear codes fine for any OBD 2 enabled truck (like the EcoDiesel).
Welcome! Glad to have you here...
Coming from an 02 is quite an upgrade.. these trucks are nice and spoils us for sure with the luxury and the MPG they offer. Good move with the lifetime warranty.