Verdict · NHTSA data
Limited data — recalls on file
NHTSA has just 0 complaints on file for the 1978 Mack U Series — 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
1 NHTSA recall campaign on file. Recall repairs are free at franchised dealers.
Defect
THE PREFABRICATED PINCH BOLT CLAMP AT THE LOWER STEERING SHAFT LOWER YOKE MAY NOT PERFORM ADEQUATELY WHEN TIGHTENED TO SPECIFICATIONS. THE CLAMP MAY THEN DEFORM AND LOSS OF CLAMPING FORCE AND STEERING SHAFT DISENGAGEMENT MAY RESULT.
Remedy
DEALER WILL RETROFIT WITH LOWER STEERING SHAFT LOWER YOKES THAT PROVIDE FOR INTEGRAL PINCH BOLT INSTALLATION IN PLACE OF PREVIOUS SEPARATELY FABRICATED CLAMP FOR THE PINCH BOLT.
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.
Yes — NHTSA lists 1 recall campaign affecting the 1978 Mack U Series. 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.