Mack R, MR +13 more: Suspension

Affects Mack R, MR, RS, FM, MH, RW, Mce, RL, U, F, DM, RD, RWS, RWL, MC · 1981–1987 — about 1K vehicles.

The hazard

NOTE: 1971 TO 1987 TRUCKS WITH NEWAY AIR RIDE DRIVE AXLE SUSPENSION. THE CHANNEL TYPE CROSSMEMBER INSTALLED WITH THE SUSPENSION CAN BE OVERSTRESSED AND CAN FAIL. THE BROKEN CROSSMEMBER CAN PROTRUDE ABOVE THE TOP OF THE FRAME AND INTERFERE WITH THE TRAILER CHASSIS COMPONENTS. THIS COULD ADVERSELY AFFECT HANDLING WHEN TURNING. ALSO, A COMPLETELY SEPARATED CROSSMEMBER WITH ATTACHED HEIGHT CONTROL VALVES COULD AFFECT THE HEIGHT OF THE SUSPENSION AIR SPRINGS. THE RESULTING LEAN COULD CAUSE LOSS OF CONTROL.

What to do

Contact your dealer; the remedy details were not included in the filing.

Critical — crash/injury risk now High — injury risk; see remedy Moderate — fix at next service Low — minor / informational