The problem
A design deficiency exists in the air dryer piping in the area of the pressure relief valve and compressor governor control link. Moisture is passed and builds up in this relief valve and control line. In freezing ambient temperatures, this moisture may freeze, allowing the chassis air system pressure to exceed 150 psi. Excessive air system pressure can cause separation of air piping connections and air system valve failure.
The fix
The dealer will relocate the air system compressor governor line and pressure relief valve to eliminate moisture accumulation.
Contacts
Vehicle description: trucks equipped with anchorlok air dryers.System: service brakes; air system and governor control line (air dryer).Consequences of defect: when this occurs, automatic application of the chassisemergency spring brakes and trailer brakes could cause loss of vehicle controlwithout prior warning and a vehicle accident.Note: owner/driver is advised not to operate vehicle if air pressure exceeds15o psi.
What to do
- Check your VIN. Enter it at nhtsa.gov/recalls - it shows whether this recall applies to your vehicle and whether the repair has been done.
- Call a dealer. Any authorized Mack dealer will do the repair free, whether or not you bought the vehicle there. Quote campaign 78V030000.
- Ask about parts and a loaner. If parts aren't available yet, ask what to do in the meantime.
- Keep your paperwork. If you paid for this repair before the recall, you may be able to get reimbursed - here's how.