PACCAR bulletin E340
What it saysKW Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. NHTSA’s full summary ↓
PACCAR filed this with NHTSA as an emissions communication dated Oct 16, 2026, received May 6, 2026, about the engine — 2 documents under this number. It names 14 model years across Kenworth and Peterbilt (2026–2027). 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.
One page for every brand it was filed under. Each brand’s bulletins: Kenworth · Peterbilt.
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.
KW Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. The engine label is now available for order and installation. PB Certain vehicle model year 2026 Peterbilt chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. The engine label is now available for order and installation.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| E340 | Service bulletin | Oct 16, 2026 | 11038715 | PDF, 357 KB |
| E340 | Emissions | Apr 10, 2026 | 11032287 | PDF, 571 KB |
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 themKenworth 7 model years
Also filed against: 2026 Kenworth L770; 2026 Kenworth T680; 2027 Kenworth T680; 2026 Kenworth T880; 2027 Kenworth T880; 2026 Kenworth W990; 2027 Kenworth W990.
Peterbilt 7 model years
Also filed against: 2026 Peterbilt 520; 2026 Peterbilt 567; 2027 Peterbilt 567; 2026 Peterbilt 579; 2027 Peterbilt 579; 2026 Peterbilt 589; 2027 Peterbilt 589.
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 group19 other manufacturer communications filed against these PACCAR models under the same component group (engine), newest first. The eight newest are listed; the rest are on the Kenworth list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| 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… |
| 41-028 | Service campaign | Sep 5, 2026 | The campaign expiration date has been extended from 10/01/2026 to 04/01/2027. |
| 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 Kenworth and Peterbilt, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is PACCAR E340 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 E340 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 E340 cover?
The manufacturer filed it against 14 model years across 2 brands (Kenworth and Peterbilt): 2026 Kenworth L770, 2026 Kenworth T680, 2027 Kenworth T680, 2026 Kenworth T880, 2027 Kenworth T880, 2026 Kenworth W990 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 16 Sep 2025 – 7 Jan 2026; built 9 Jun 2025 – 7 Jan 2026 — the build date is on the certification label in the driver’s door jamb.