VehicleVerdict

2003 Mack DMM problems

Verdict · NHTSA data

Limited data — recalls on file

NHTSA has just 0 complaints on file for the 2003 Mack DMM — too few to judge reliability from owner reports alone — but one recall campaign applies to this year, so any used example should have its VIN checked for completed recall work.

0

NHTSA complaints

1

Recalls

0

Investigations

0

Crash-involved

0

Fires reported

0

Injuries

0

Deaths

—

NCAP overall

Does the 2003 Mack DMM have recalls?

1 NHTSA recall campaign on file. Recall repairs are free at franchised dealers.

03V253000BrakesJuly 17, 2003 · 1,232 units

Defect

CERTAIN HEAVY DUTY VEHICLES FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS." IMPROPER SEATING OF THE CHECK VALVE RETAINER IN THE BRASS FITTING HOUSING HAS OCCURRED. IT IS POSSIBLE FOR THE AIR BRAKE SYSTEM PRESSURE TO PUSH THE CHECK VALVE INTERNAL PARTS INTO THE PRIMARY SYSTEM RESERVOIR AND A VEHICLE OPERATOR WOULD NOT KNOW THAT THIS HAS HAPPENED.

Consequence

IN THIS CONDITION, THE VEHICLE WOULD NOT MEET THE EMERGENCY REQUIREMENTS OF THE STANDARD.

Remedy

DEALERS WILL REPLACE THE CHECK VALVE. OWNER NOTIFICATION BEGAN NOVEMBER 26, 2003. OWNERS SHOULD CONTACT MACK AT 1-610-709-3337.

2003 Mack DMM — common questions

Is the 2003 Mack DMM reliable?

The record is thin — 0 NHTSA complaints — so owner-report data can't strongly confirm reliability either way, though 1 recall should be verified as completed.

Does the 2003 Mack DMM have recalls?

Yes — NHTSA lists 1 recall campaign affecting the 2003 Mack DMM. Recall repairs are free at franchised dealers; check the VIN at nhtsa.gov/recalls to confirm the work was done.

Related

Based on NHTSA ODI data through June 2026. Complaints are consumer-reported and unverified. Updated July 5, 2026.

Compiled by Sharon Ben-Moshe, Founder.