Service bulletins for the 2021 Peterbilt 389
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.
74 on file from NHTSA, as of 2026-10-19.
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Only bulletins with component: Suspension are shown. Show all
| 16-044 | 2024-08-02. Service bulletin. SUSPENSION. Fix As Fail The height control valve (HCV) rod on vehicles with low air leaf suspensions is prone to toggling over center during rough road conditions. With full suspension articulation, HCV bracket flexes and toggles over center the HCV linkage, which results in either deflated airbags or makes them unable to inflate. Fix-as-fail start date is 07/30/2024. |
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| 14-043 | 2022-10-05. Service bulletin. SUSPENSION. Fix-As-Fail On certain chassis with Low Air Leaf Suspension or Low-Low Air Leaf Suspension, the Height Control Valve (HCV) arm may be rubbing on other components when the bend in the arm is facing outboard. Flipping the bend in the HCV arm inboard prevents the rub. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.