Kenworth, Haldex and Peterbilt preliminary evaluation PE21018
Haldex Brake Chamber Failures. NHTSA’s Office of Defects Investigation opened this preliminary evaluation about the chamber on 6 model years (2015–2019). Opened Jul 16, 2021, closed Oct 10, 2025 after 4.2 years without a recall. closed
What NHTSA says
Source: Office of Defects Investigation, as filedThe Office of Defects Investigation (ODI) opened this Preliminary Evaluation (PE21018) based on eleven Vehicle Owner Questionnaires (VOQ). These VOQs included seven wheel-end fires on various Kenworth and Peterbilt trucks. Several of the VOQs were submitted by a maintenance facility stating that the fires were due to power spring fractures within brake chambers manufactured by Haldex Commercial Vehicle Systems (Haldex). According to the reports, the fractured spring punctured the brake chamber diaphragm, resulting in a partial loss of compressed air to the park brakes, causing the brakes to drag and overheat. ODI sent an information request letter to Haldex on August 3, 2021. On October 17, 2021, Haldex submitted a complete response. In this investigation, ODI analyzed thousands of warranty claims as well as fleet reports of brake chamber replacements. ODI gathered information from multiple vehicle manufacturers and reviewed legal testimony alleging defects and laboratory reports that raised concerns about spring failures initiated by corrosion. ODI found that spring failures were often detectable as soon as they occurred. In the subject incidents, after detecting the failures, some operators continued driving to a maintenance facility rather than stopping and waiting for a mobile technician to address the issue, increasing the risk of fire. While over twenty entities purchased the subject component from Haldex, the VOQs that ODI received involved only PACCAR vehicles. Haldex completed replacement campaigns for several fleets operating PACCAR vehicles, reducing the risk of further failures. Brake chambers have a limited service life. Industry guidance generally recommends replacement every two to four years depending on operating conditions, with some manufacturers and fleets recommending even shorter intervals. Vehicles operating in salt-belt states—where the majority of VOQs originated—require more frequent replacement than vehicles in less corrosive environments. Haldex’s standard warranty is four years and unlimited mileage. ODI determined that the average time in service for warranty claims was 4.9 years and 260,000 miles. Currently, all of the chambers subject to this investigation are between five and ten years old. Given the absence of recent failures and because the subject components are now older than their expected service life, ODI is closing this investigation. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The Agency reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
A Preliminary Evaluation is the first formal stage: NHTSA has decided the complaints and other information it screened are worth a closer look, and asks the manufacturer for its own data on the condition. The summary is the agency’s own text from its investigation file, unedited; the resumes carrying the full reasoning are linked below.
The paperwork NHTSA filed
Source: every document on this action, at nhtsa.gov- Opening resume — ODI’s own summary of why it opened this — the subject, what prompted it, and the vehicles in scope.
- Closing resume — ODI’s own summary of why it closed this, and what it concluded.
| Document | Code | Filed | At NHTSA |
|---|---|---|---|
| Opening resume | INOA | 2021 | |
| Closing resume | INCLA | 2021 | |
| Information request to the manufacturer | INIM | 2021 | 13 files 12345678910111213 |
| Manufacturer's response — data | INRD | 2021 | |
| Memo granting a response extension | INRE | 2021 | 3 files 123 |
| Filed document | INSR | 2021 | |
| Confidential business information notice | INCBC | 2021 | 2 files 12 |
| Correspondence | INOT | 2021 | 3 files 123 |
| Filed document | INCV | 2021 |
These are NHTSA’s own files, served from the agency’s site — the resumes are what ODI wrote when it opened and closed the action, and the rest is the correspondence behind them, including what the manufacturer sent when the agency asked. They are linked, not copied: where a document names the people who wrote in, that redaction is the agency’s to make and its copy is the one you should read.
What owners had already reported
Source: complaints on file the day it openedWhen NHTSA opened this on Jul 16, 2021, owners had filed 34 complaints with the agency about the model years above. Owner complaints are the agency’s main early signal: ODI screens them, and a Preliminary Evaluation is usually where a pattern in them ends up.
This is what the complaint file held on that date, not a claim about which reports prompted the investigation — NHTSA’s complaint records carry no investigation number, so nobody can make that link from the data alone. The opening resume linked above names the reports ODI itself cited. Complaint records on this site begin with 2016.
What this means for an owner
Source: and what happens nextAn investigation is not a finding that a defect exists, and it puts no duty on anyone. NHTSA opens a Preliminary Evaluation when complaints and other reports suggest a condition worth asking the manufacturer about; it upgrades to an Engineering Analysis when the answers warrant testing; it closes either when it recommends a recall, when the manufacturer recalls on its own, or when no defect trend is found. The agency’s own goals are about four months for a petition, eight for a Preliminary Evaluation or a Recall Query and eighteen for an Engineering Analysis; many run longer.
This one closed without a recall. That means NHTSA found no defect trend it chose to act on at the time, or the manufacturer addressed the condition another way (a service campaign or a bulletin, which have their own pages). A closed file can be reopened if new reports arrive.
Model years it names
Source: as NHTSA filed themAlso named: 2015 Kenworth T680; 2016 Kenworth T680; 2017 Kenworth T680; 2018 Kenworth T680; 2019 Kenworth T680; 2017 Peterbilt 579.
A vehicle page’s investigation list carries the same action; a name here is the scope NHTSA opened, not a list of affected VINs.
Common questions
Source: NHTSA Office of Defects InvestigationIs PE21018 a recall?
No. A preliminary evaluation is NHTSA asking questions, not a recall. A safety recall carries an NHTSA campaign number and a duty to repair for free; this one closed without one. Whether one particular vehicle has an open recall is a VIN question at nhtsa.gov/recalls.
Is PE21018 still open?
No. It closed on Oct 10, 2025 without a recall.
Which vehicles does PE21018 cover?
NHTSA opened it on 6 model years: 2015 Kenworth T680, 2016 Kenworth T680, 2017 Kenworth T680, 2018 Kenworth T680, 2019 Kenworth T680, 2017 Peterbilt 579. That is the scope of the inquiry, not a list of affected vehicles; a recall, if one follows, defines its own population by VIN.