At a glance
What can fail
On certain cutaway chassis vehicles with 6.8L engines and trailer brake controllers, the trailer brakes may not activate when you press the brake pedal while towing. You won't be warned, which could lengthen stopping distance.
What the fix does
Dealers will reprogram the powertrain control module to fix the trailer brake activation issue.
Summarized — see the official notice for exact wording, dates, and contacts.