Cm871 repeated same injector failure

[in2trux]

Rawze is always thinking! Are you putting the new injector in #6 or moving an old one? By now you should have all new injectors!
If you move one from another cylinder and it fails that is a symptom, not the problem.
Is the same shop doing the troubleshooting? Leak test should have been done already.

It seems that at 500k, just when warranty runs out lot's of problems surface. That is the beauty of this forum, shared experience with the same engine.
The whole lot of us have seen lots of problems and have worked past them.

I would be looking at the injector harness. Replacing 2 rear bank fueling and metering actuators would be throwing money at it but you're going to need them sooner rather than later.

The 2637 code will haunt you constantly. The white puffs of smoke are from it trying to regen, unless the doser is leaking fuel or coolant.
Ultimately there is only, the final solution, if you want to keep your sanity and make money.