Peterbilt bulletin E327
What it says"Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. NHTSA’s full summary ↓
Peterbilt filed this with NHTSA as an emissions communication dated Feb 27, 2025, received Mar 4, 2025, about the engine. It names 30 model years (2021–2025). An emissions communication is not a safety recall — there is no NHTSA campaign number and no federal requirement — but it is usually work the manufacturer pays for on the vehicles it names; the dealer checks the VIN against the manufacturer’s list.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationWhat it applies to, as the document itself states it — the build window in the manufacturer’s own words, read by machine from the PDF NHTSA serves. The build date is on the certification label in the driver’s door jamb; the dealer settles a borderline vehicle by its VIN.
"Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. PCI-2 software on these chassis must be reverted from NA202 to NA201 (Pack 2 injectors) or from NA206 to NA191 (Pack 1 injectors) to prevent incorrect STOP lamp display.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| E327 | Emissions | Feb 27, 2025 | 11014768 | PDF, 309 KB |
What the document itself lists
Labour operation and the time the manufacturer allows
| Operation | Description | Time |
|---|---|---|
| 2302109PE | X Supplier Code PACCAR SRT Code B25-07A | 0.4 hrs |
Read by machine from the document NHTSA serves (4 pages), read Sep 30, 2026. A part number is shown only where it matches Peterbilt’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote.
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themAlso filed against: 2021 Peterbilt 365; 2022 Peterbilt 365; 2023 Peterbilt 365; 2024 Peterbilt 365; 2025 Peterbilt 365; 2021 Peterbilt 367; 2022 Peterbilt 367; 2023 Peterbilt 367; 2024 Peterbilt 367; 2025 Peterbilt 367; 2021 Peterbilt 389; 2022 Peterbilt 389; 2023 Peterbilt 389; 2024 Peterbilt 389; 2025 Peterbilt 389; 2021 Peterbilt 520; 2022 Peterbilt 520; 2023 Peterbilt 520; 2024 Peterbilt 520; 2025 Peterbilt 520; 2021 Peterbilt 567; 2022 Peterbilt 567; 2023 Peterbilt 567; 2024 Peterbilt 567; 2025 Peterbilt 567; 2021 Peterbilt 579; 2022 Peterbilt 579; 2023 Peterbilt 579; 2024 Peterbilt 579; 2025 Peterbilt 579.
None of these model years has a page on this site (it covers EPA-certified cars, trucks and SUVs from 2016), so the bulletin is listed here on its own.
More bulletins about the engine
Source: same model, same component group16 other manufacturer communications filed against these Peterbilt models under the same component group (engine), newest first. The eight newest are listed; the rest are on the Peterbilt list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| E340 | Emissions | Oct 16, 2026 | KW Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. The engine labe… |
| P001 | Service campaign | Sep 11, 2026 | "KW: The chassis list has been updated to include 1 chassis. The total chassis count is now 53. A link to the PACCAR Powertrain Prognostics… |
| P003 | Service campaign | Sep 3, 2026 | "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to incl… |
| P002 | Service campaign | Sep 3, 2026 | "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to incl… |
| E316 | Service campaign | Aug 1, 2026 | 235 chassis have been removed from the chassis list and unflagged in PRWS due to expiration of applicable warranty coverage. 5 chassis have… |
| E335 | Emissions | Jul 18, 2026 | Expiration Date Format Update - Certain EPA21 compliant PACCAR MX-13 engines were built with intake valve springs that could fail. This fail… |
| CE033 | Warranty extension | Jun 25, 2026 | "KW & PB 14 fuel injector part numbers (seven for MX-11 and seven for MX-13 engines) have been added to this warranty policy." |
| CE031 | Warranty extension | Jun 24, 2026 | "KW & PB 14 fuel injector part numbers (seven for MX-11 and seven for MX-13 engines) have been added to this warranty policy." |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Peterbilt, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Peterbilt E327 a recall?
No. A emissions communication is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls.
Is the E327 repair free?
A emissions communication is usually paid by the manufacturer on the vehicles it names, within the terms and time limit the document sets; the dealer checks the VIN against the manufacturer’s list.
Which vehicles does E327 cover?
The manufacturer filed it against 30 model years: 2021 Peterbilt 365, 2022 Peterbilt 365, 2023 Peterbilt 365, 2024 Peterbilt 365, 2025 Peterbilt 365, 2021 Peterbilt 367 and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone. The document itself sets the build window: built 9 Apr 2020 – 19 Jan 2024 — the build date is on the certification label in the driver’s door jamb.