1978 MACK U

5 recalls, 0 complaints - 27 TSBs

79V133000 May 31, 1979
ENGINE AND ENGINE COOLING:ENGINE
Defect Description
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... Read more
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.
23,000 vehicles affected
Manufacturer: MACK TRUCKS, INCORPORATED
79V082000 Apr 3, 1979
STEERING: STEERING WHEEL/HANDLE BAR
Defect Description
AN IMPROPER PINCH BOLT AND NUT MAY HAVE BEEN USED IN THE CLAMPING OF THE STEERING SHAFT TO THE STEERING GEAR INPUT SHAFT. DUE TO CLAMPING FORCE LOADS APPLIED AT THE BOLT, THE NUT COULD YIELD, RESULTING IN LOOSENESS OF THE INPUT SHAFT YOKE. SHOULD THIS CONDITION GO UNNOTICED, SPLINE WEAR COULD CAUSE... Read more
Remedy
VEHICLES WILL BE INSPECTED AND, IF NECESSARY, THE CORRECT FASTENERS WILL BE INSTALLED AT NO CHARGE TO OWNER.
12,000 vehicles affected
Manufacturer: MACK TRUCKS, INCORPORATED
79V017000 Jan 12, 1979
SUSPENSION:MULTIPLE AXLE
Defect Description
A CASTING DEFICIENCY EXISTS IN THE LOWER SECTION OF THE CAPS RESULTING IN A REDUCTION IN THE THICKNESS OF THE MATERIAL. FAILURE OF A CAP CAN ALLOW THE END OF THE REAR SPRING TO DETACH FROM THE AXLE HOUSING.
Remedy
DEALER WILL INSPECT AND, IF NECESSARY, REPLACE ANY OF THE SPRING INSULATOR CAPS FOUND TO BE DEFECTIVE. THIS WILL BE DONE AT NO COST TO OWNER.
4,000 vehicles affected
Manufacturer: MACK TRUCKS, INCORPORATED
78V210000 Oct 3, 1978
SERVICE BRAKES, AIR:ANTILOCK:INTERCONNECTING ASSEMBLY(WIRING)
Defect Description
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... Read more
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.
19,370 vehicles affected
Manufacturer: MACK TRUCKS, INCORPORATED
78V031000 Feb 9, 1978
SUSPENSION:MULTIPLE AXLE
Defect Description
THE TEE BRACKET, WHICH IS MOUNTED ON THE FRONT AXLE OF THE BOGIE, MAY FAIL DUE TO VIBRATION BROUGHT ON BY ROAD SURFACE IRREGULARITIES. BRACKET FAILURE WOULD LEAVE THE TEE BRACKET UNSUPPORTED AND CAUSE BROKEN HOSE CONNECTOR FITTINGS. THIS WOULD RESULT IN AUTOMATIC APPLICATION OF THE SPRING EMERGENCY ... Read more
Remedy
THE DEALER WILL REPLACE THE DEFECTIVE BRACKET WITH A REDESIGNED VERSION.
33,000 vehicles affected
Manufacturer: MACK TRUCKS, INCORPORATED

No complaints found for this vehicle.

Technical Service Bulletins, 1978 MACK U

27 manufacturer communications from 22 unique bulletins. TSBs describe known problems and recommended fixes from the manufacturer.

Most Affected Components

ComponentBulletins
060000 ENGINE AND ENGINE COOLING12
110000 ELECTRICAL SYSTEM4
100000 POWER TRAIN4
180000 VEHICLE SPEED CONTROL2
980000 UNKNOWN OR OTHER2
251000 ELECTRONIC STABILITY CONTROL:AUTOMATIC (ASC)1
020000 SUSPENSION1
350000 EQUIPMENT1
KC-750 Jun 28, 2022
060000 ENGINE AND ENGINE COOLING
US10 Emission Engines - Diagnostic Trouble Code ( DTC ) SPN 1231 FMI 9 Troubleshooting.
KC-745 Jun 22, 2022
100000 POWER TRAIN
Automated Manual Transmission ( AMT ) I-Shift / mDRIVE - Ribbon Harness Replacement - Speed Sensor Bolts, Possible Fault Codes P1058 - 21 Or MID 130 PID 161 FMI 1
KC-2112 Jun 21, 2022
110000 ELECTRICAL SYSTEM
Programming Failure - Chassis With Cummins Engine And An Allison Transmission
KC-2112 Jun 21, 2022
100000 POWER TRAIN
Programming Failure - Chassis With Cummins Engine And An Allison Transmission
KC-2112 Jun 21, 2022
060000 ENGINE AND ENGINE COOLING
Programming Failure - Chassis With Cummins Engine And An Allison Transmission
KC-2143 Jun 21, 2022
180000 VEHICLE SPEED CONTROL
(Back Office) - Cruise Control Inoperative After Updating Software VECU5 Without ESP Package (UESP).
KC-2116 May 26, 2022
060000 ENGINE AND ENGINE COOLING
NOx Sensor Troubleshooting Guide - US10+OBD13 And Newer Emissions
KC-2131 May 26, 2022
060000 ENGINE AND ENGINE COOLING
USE FOR NEW VEHICLES (US21+OBD22 Emissions) - Intermittent Diagnostic Trouble Codes U02A3, U029D, U029E
KC-2158 May 26, 2022
060000 ENGINE AND ENGINE COOLING
Selective Catalytic Reduction (SCR) Muffler Troubleshooting Guide - US10+OBD13 And Newer Emissions
KC-2171 May 26, 2022
060000 ENGINE AND ENGINE COOLING
Temperature Sensor Troubleshooting Guide - US10+OBD13 And Newer
KC-2165 May 26, 2022
060000 ENGINE AND ENGINE COOLING
DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions
KC-714 May 25, 2022
060000 ENGINE AND ENGINE COOLING
Mack Chassis - Diagnostic Trouble Codes ( DTC's ) - P020113, P020213, P020313, P020413, P020513, P020613, Cylinders 1 Through 6 Injector A Open Circuit
KC-699 May 24, 2022
110000 ELECTRICAL SYSTEM
Mack Chassis - Bendix Vendor Configuration Program ( VCP ) Software Download Information
KC-698 May 24, 2022
060000 ENGINE AND ENGINE COOLING
Mack Chassis - Diesel Exhaust Fluid ( DEF ) System Cleaning/Flush After DEF Pump Failure Or System Contamination
KC-686 May 20, 2022
180000 VEHICLE SPEED CONTROL
(Back Office Only) Mack Chassis - Cruise Control Inoperative After Disabling The Electronic Stability Program (ESP)
KC-686 May 20, 2022
251000 ELECTRONIC STABILITY CONTROL:AUTOMATIC (ASC)
(Back Office Only) Mack Chassis - Cruise Control Inoperative After Disabling The Electronic Stability Program (ESP)
KC-663 May 18, 2022
060000 ENGINE AND ENGINE COOLING
Emcon (Spark Assist) Engine Aftertreatment System Troubleshooting Check Sheet - US07 Emissions
KC-653 May 17, 2022
060000 ENGINE AND ENGINE COOLING
Low Oil Pressure Diagnostic Process For 11 Liter Engines
KC-648 May 17, 2022
980000 UNKNOWN OR OTHER
Mack - PTO Pump Speed Calculator
KC-648 May 17, 2022
100000 POWER TRAIN
Mack - PTO Pump Speed Calculator
KC-2169 May 16, 2022
110000 ELECTRICAL SYSTEM
Low Voltage Disconnect (LVD), Function Description
KC-2170 May 16, 2022
020000 SUSPENSION
Electronically Controlled Suspension (ECS) Losing Air Pressure
KC-2172 May 16, 2022
110000 ELECTRICAL SYSTEM
No Start Condition After Over The Air Programing - VECU5 No Start "Safe State"
KC-2172 May 16, 2022
980000 UNKNOWN OR OTHER
No Start Condition After Over The Air Programing - VECU5 No Start "Safe State"
KC-2161 May 13, 2022
060000 ENGINE AND ENGINE COOLING
DEF Pump Cycling periodically Hours After Key Off
KC-627 May 9, 2022
350000 EQUIPMENT
Premium Tech Tool ( PTT ) Training Materials And Support Tools
KC-626 May 9, 2022
100000 POWER TRAIN
Mack Chassis - Vehicles Equipped With An Automated Manual Transmission Model F ( AMT-F, mDrive ), Premium Tech Tool ( PTT ) Gearbox Calibration Failure; Gearbox Calibration Operation Stops And Fails At 33% When Run With Transmission Removed

MACK U - All Years Overview

Complete safety history for the MACK U across all model years (1967, 1992).

57 Total Recalls
0 Total Complaints
0 Investigations
0 Reported Crashes
0 Reported Fires
0 Reported Deaths

MACK U - Year by Year

Compare recalls and complaints across model years. Click any year to see full details.

Year Recalls Complaints
1992 1 0 View
1991 1 0 View
1990 1 0 View
1989 2 0 View
1988 1 0 View
1987 1 0 View
1979 1 0 View
1978 (current) 5 0
1977 8 0 View
1976 3 0 View
1975 6 0 View
1974 6 0 View
1973 5 0 View
1972 4 0 View
1971 5 0 View
1970 3 0 View
1969 2 0 View
1968 1 0 View
1967 1 0 View

Other MACK Models

Model Recalls Complaints
GRANITE (GU) 127 3 View
CF 104 0 View
RD 103 8 View
DM 95 1 View
PINNACLE (CXU) 92 5 View
CH 91 8 View
R 89 0 View
GRANITE (GR) 83 10 View