At a glance
What can fail
Severe brake chatter can cause cracks to develop in the welds of the front axle brake chamber mounting brackets where the S-cam tube attaches. A cracked bracket could fail, resulting in loss of front wheel braking and reduced steering control.
What the fix does
Reinforced front axle brake chamber mounting brackets will be installed, and a front brake limiting valve will be added if not already fitted.
Summarized — see the official notice for exact wording, dates, and contacts.