1978 Mack RM problems

Verdict · NHTSA data

Limited data — recalls on file

NHTSA has just 0 complaints on file for the 1978 Mack RM — too few to judge reliability from owner reports alone — but 2 recall campaigns apply to this year, so any used example should have its VIN checked for completed recall work.

NHTSA complaints

Recalls

Investigations

Crash-involved

Fires reported

Injuries

Deaths

—

NCAP overall

How does 1978 compare to other RM years?

RM NHTSA complaints by model year, 1978 highlighted. Red bars are years to avoid.

See all RM years to avoid →

Does the 1978 Mack RM have recalls?

2 NHTSA recall campaigns on file. Recall repairs are free at franchised dealers.

79V133000EngineMay 31, 1979 · 23,000 units

Defect

IN THE EVENT OF TURBOCHARGER COMPRESSOR WHEEL FAILURE, ONE OR MORE OF THE FOUR CAPSCREWS THAT HOLD THE TURBOCHARGER TOGETHER MAY BE STRUCK BY PARTS OF THE COMPRESSOR WHEEL, RESULTING IN THE CAPSCREWS BEING DAMAGED. IF THESE CAPSCREWS ARE DAMAGED TO THE POINT THAT THEY ALLOW THE COMPRESSOR BACK PLATE TO DISLOCATE FROM THE TURBOCHARGER BEARING HOUSING, ENGINE LUBRICATING OIL MAY BE ALLOWED TO ESCAPE UNDER PRESSURE, CONTACTING THE ENGINE EXHAUST MANIFOLD SECTIONS OR TURBOCHARGER TURBINE HOUSING.

Remedy

DEALER WILL INSTALL A SHIELD FOR THE HEADS OF THE FOUR CAPSCREWS, ALONG WITH STRONGER SAE 8 GRADE 8 CAPSCREWS, IF NECESSARY, AT NO COST TO OWNER.

78V210000BrakesOctober 3, 1978 · 19,370 units

Defect

DELAYS OF UP TO ABOUT 2 SECONDS MAY EXIST IN THE BRAKE APPLICATION TIMES TO THE BRAKES ON THE BOGIE AXLES IN THE PRESENCE OF CERTAIN TYPES OF WHEEL SPEED SENSOR SIGNAL DISCONTINUITIES OR DISTORTIONS THAT MAY OCCUR AS A RESULT OF SENSOR WIRE FAILURE. THIS CONSTITUTES A NON-COMPLIANCE TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS".

Remedy

DEALER WILL INSTALL NEW WHEEL SPEED SENSORS THAT INCORPORATE IMPROVED WIRING AND THE PRESENT BOGIE ANTI-WHEEL LOCK SYSTEM WILL BE CHANGED TO AN AXLE-TO-AXLE SYSTEM FOR IMPROVED RELIABILITY.

1978 Mack RM — common questions

Is the 1978 Mack RM reliable?

The record is thin — 0 NHTSA complaints — so owner-report data can't strongly confirm reliability either way, though 2 recalls should be verified as completed.

Does the 1978 Mack RM have recalls?

Yes — NHTSA lists 2 recall campaigns affecting the 1978 Mack RM. Recall repairs are free at franchised dealers; check the VIN at nhtsa.gov/recalls to confirm the work was done.

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

Compiled by Sharon Ben-Moshe, Founder.

How does 1978 compare to other RM years?

Does the 1978 Mack RM have recalls?

1978 Mack RM — common questions

Is the 1978 Mack RM reliable?

Does the 1978 Mack RM have recalls?

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