try updating to the latest version 2.5.3

2.5.1 is what it is right now

My LBZ will knock when its really cold, even after engine temps are up, you still get a little injection knock/rattle

This knock comes and go's,i have had the truck for 2 years and heard it knock cold and hot but this is totally different,like a rod but it cant be cause it comes and go's.

how does the truck run otherwise?? low on power? extra smoke? smell of fuel? have you checked the oil?

truck runs normal,no smoke ever,same power,no smell,oil was changed 1500 miles ago and stilll full,will hold 80psi plus cold and 40-60 warm

still getting engine codes?:humm:

have not checked but i dont think i will cause i have not had the BD on it an been really easy on it.

the only next culprit that I can think of is maybe the CP3... but Im not sure, I wish there were more duramax guys on this site:td: