Service campaign S4558 202506
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
| Type | Service campaign |
|---|---|
| NHTSA id | 11020159 |
| Published by NHTSA | 2025-07-03 |
| Manufacturer's number | S4558 202506 |
| Manufacturer's date | 2025-06-18 |
| NHTSA component | POWER TRAIN |
NHTSA's summary
Mack trucks has determined that certain model year 2021-2024 PI models built with 4.19 rear axle ratios could experience elevated axle oil temps under high road speeds. To correct this issue the 4.19 ratio carriers need to be swapped to 3.79 ratio carriers. Follow the instructions below to replace both carriers with new ones.
The document
The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.
Components
Transmission and driveline
| MACK PINNACLE (PI/PN) | 2021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it) |
|---|
Listing a model year does not mean every vehicle of it is concerned: the document says which.
| TSB M-913-001 202609 | 2026-10-02. Service bulletin. Parker engine-mounted hydraulic pump service bulletin. |
|---|---|
| CBR 2573-1 202604 | 2026-05-05. Service bulletin. CBR - Mack Chassis - Through Shaft Bearing Retainer Breakage On Mack Carriers. |
| CBR 2362-3 202604 | 2026-05-04. Service bulletin. CBR - Mack Carrier Nut Adhesive Change. |
| CBR 2218-6 032026 | 2026-04-02. Service bulletin. CBR - Parker F3 Hydraulic Pump Troubleshooting. |
| CBR 2464-1 202505 | 2025-06-02. Service bulletin. Mack Chassis - Rear Axle Overheat |
| CBR-2387 202409 | 2024-10-04. Service bulletin. CBR: Vehicles Equipped With A Lift Axle - Wheel Speed Fault Code SPN 793, SPN 794 Set When Axle Is Up |
| CBR-2258 202409 | 2024-10-03. Service bulletin. CBR: Diagnostic Trouble Code (DTC) P107471 - AMT-F |
| CBR-731 202409 | 2024-10-03. Service bulletin. CBR: Automated Manual Transmission (AMT) Model D or F (mDrive and I-Shift, AMT-D, AMT-F) - Transmission Oil Leakage From Transmission Input Shaft Seal Or Output Shaft Seal - US10 And Newer Emissions, Common Model Years 2010 And Newer |
| CBR-2391 202408 | 2024-09-04. Service bulletin. CBR: Diagnostic Trouble Code (DTC) U010187- Lost Communication With TECU |
| CBR-343 202408 | 2024-09-04. Service bulletin. CBR: Mack chassis with an mDRIVE transmission, there have been reports of complete shift assemblies and TECUs being replaced due to technicians being unable to pinpoint the source of the air leak. |