# Service bulletin 27\-012

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 bulletin
- NHTSA id: 11033380
- Published by NHTSA: 2026\-06\-03
- Manufacturer's number: 27\-012
- Manufacturer's date: 2026\-05\-26
- NHTSA component: POWER TRAIN

## NHTSA's summary

KW: A Transmission Control Module \(TCM\) software update is now available for certain T680, T880, and W990 chassis with Eaton Endurant transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. Please see the Eaton bulletin TAIB\-1015 in the Attachments section for details. PB: A Transmission Control Module \(TCM\) software update is now available for certain Model 567, 579, and 589 chassis with Eaton Endurant transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. Please see the Eaton bulletin TAIB\-1015 in the Attachments section for details.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11033380-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11033380-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Transmission and driveline

## Vehicles listed

- 2025 to 2026 KENWORTH T680
- 2025 to 2026 KENWORTH T880
- 2025 KENWORTH W900B
- 2010 KENWORTH W900S
- 2025 to 2026 PETERBILT 567
- 2025 to 2026 PETERBILT 579
- 2025 to 2026 PETERBILT 589

## Recalls for the same vehicles and component

- [24V190000](/recalls/nhtsa/24V190000.md), 2024-03-20: POWER TRAIN:AUTOMATIC TRANSMISSION:LEVER AND LINKAGE:COLUMN SHIFT

## Other bulletins for the same vehicles and component

- [T024](/bulletins/11033925.md), 2026-06-17, Service bulletin: POWER TRAIN. "KW \& PB: New software is available for download. The DAVIE4 cache must be cleared before attempting to reprogram a chassis that is experiencing problems to ensure the latest version of software is installed. Follow all steps in the attached procedures before submitting a TCS case."
- [T\-024](/bulletins/11033923.md), 2026-06-17, Service bulletin: POWER TRAIN. The repair procedure has been updated to include diagnostic steps.
- [27\-012](/bulletins/11033917.md), 2026-06-17, Service bulletin: POWER TRAIN. The attachment for Eaton bulletin TAIB\-1015 has been updated to the latest version to improve process flow.
- [T024](/bulletins/11033379.md), 2026-06-03, Service bulletin: POWER TRAIN. KW: A Transmission Control Module \(TCM\) software update is now available for certain T280, T380, T480, T680, T880, and W990 chassis with PACCAR TX\-12 and TX\-18 transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. PB: A Transmission Control Module \(TCM\) software update is now available for certain Model 537, 548, 567, 579, and 589 chassis with PACCAR TX\-12 and TX\-18 transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails.
- [24PBE\_24KWE](/bulletins/11028308.md), 2026-02-05, Warranty extension: POWER TRAIN; ELECTRICAL SYSTEM. 24PBE\_24KWE RH Shift Stalk Update Warranty section has been updated with revised verbiage for picture requirements.
- [24PBE/KWE](/bulletins/11027063.md), 2026-01-06, Warranty extension: POWER TRAIN; ELECTRICAL SYSTEM. The right\-hand shift stalk may have an improper wire harness terminal crimp within the wire harness connector. Loss of communication between the right\-hand shift stalk and the vehicle may result in the vehicle being disabled after it comes to a stop, thereby increasing the risk of crash or injury. A warning will appear on the dash display when communication is lost, including transmission or engine warnings, “\!” next to DNR/DNRP indicator, “\-“ in the DNR/DNRP indicator, and/or chimes, depending upon whether you are operating a diesel/gas or battery electric vehicle.
- [27\-011](/bulletins/11027060.md), 2026-01-06, Service bulletin: POWER TRAIN. A transmission control module \(TCM\) software update is now available for certain T680 / T880 / W900 / W990 chassis with Eaton Endurant transmissions running TCM software version 5516372, where the PTO fails to operate or engage. Please see the attached Eaton bulletin TAIB\- 1021 in the Attachments section of this bulletin for complete details.
- [24KWE](/bulletins/11026414.md), 2025-12-05, Service campaign: ELECTRICAL SYSTEM; POWER TRAIN. The right\-hand shift stalk may have an improper wire harness terminal crimp within the wire harness connector. Loss of communication between the right\-hand shift stalk and the vehicle may result in the vehicle being disabled after it comes to a stop, thereby increasing the risk of crash or injury. A warning will appear on the dash display when communication is lost, including transmission or engine warnings, “\!” next to DNR/DNRP indicator, “\-“ in the DNR/DNRP indicator, and/or chimes, depending upon whether you are operating a diesel/gas or battery electric vehicle.
- [E319](/bulletins/11010897.md), 2024-12-02, Service campaign: POWER TRAIN. Emissions Campaign Engine Model Year 2024 may not be displayed correctly on the PACCAR MX Engine Label. New and improved PACCAR MX Engine Labels are now available to be installed. Campaign start date is 11/26/2024
- [46\-011](/bulletins/11010890.md), 2024-12-02, Service bulletin: ELECTRICAL SYSTEM; POWER TRAIN. Some 579EV and 520EV BEV trucks may have loose or improperly torqued ESS gland nuts. This may cause an intermittent warning light on the dash display.

JSON: [/v1/bulletins/11033380](/v1/bulletins/11033380)

[Report an error on this page](https://github.com/wenmar-pro/wenmar-open/issues/new?template=data_correction.yml&title=Data%20correction%3A%20Service%20bulletin%2027-012&page=https%3A%2F%2Fopen.wenmarpro.com%2Fbulletins%2F11033380&vehicle=Service%20bulletin%2027-012)