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Service bulletin PIP5981C

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11012020
Published by NHTSA2024-12-20
Manufacturer's numberPIP5981C
Manufacturer's date2024-12-16
NHTSA componentUNKNOWN OR OTHER; POWER TRAIN

NHTSA's summary

This Preliminary information communicates ordering process for the front and rear drive units are on restriction for all listed EV vehicles for engineering review.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Transmission and driveline

Vehicles listed
BRIGHTDROP 600 ELCV2023 to 2024
BRIGHTDROP ZEVO 4002024 (the catalog's model; the bulletin names a series or trim of it)
BRIGHTDROP ZEVO 6002023, 2024 (the catalog's model; the bulletin names a series or trim of it)
CADILLAC ESCALADE IQ2025
CADILLAC LYRIQ2023, 2024, 2025
CADILLAC OPTIQ2025
CHEVROLET BLAZER EV2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET BRIGHTDROP 4002025 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET BRIGHTDROP 6002025 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET EQUINOX EV2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO EV2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
GMC HUMMER EV PICKUP2022, 2023, 2024, 2025
GMC SIERRA EV2024, 2025 (the catalog's model; the bulletin names a series or trim of it)

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
N252502891-012026-08-20. Service campaign. Certain vehicles may have a condition in which the internal differential nut was cross threaded or missing during assembly. Dealers will review the vehicles service history in IVH, and if necessary, replace the rear electric drive transmission module.
N252502890-012026-08-20. Service campaign. Certain vehicles may have a condition in which the internal differential nut was cross threaded or missing during assembly. Dealers will review the vehicles service history in IVH, and if necessary, replace the front electric drive transmission module.
N242471460-012026-08-20. Service campaign. Certain vehicles may have been built with an Electric Drive Unit mounting bolt that is too long, causing damage to the Drive Unit case. Dealers will inspect and replace the Electrical Drive Unit if necessary.
24-NA-2622025-12-03. Service bulletin. This bulletin helps aid the tech in possible 10L100 transmission noise that may be normal or abnormal depending on the concern noted.
25-NA-1082025-10-27. Service bulletin. This bulletin provides a procedure to inspect and verify the drive shafts are over extending past the 5mm tolerance, causing the customers concern of a fluid leak under the vehicle.
24-NA-1332025-10-25. Service bulletin. This informational bulletin provides information on Wheel Drive Shaft Retention Snap Ring Design Change.
N2525177902025-10-14. Service campaign. Certain vehicles, equipped with 8L80 or 8L90 Transmissions, may have a condition in which the reaction carrier cracks. Dealers are to replace the reaction carrier.
22-NA-1822025-09-27. Service bulletin. This service bulletin advises the technician to check if the transmission cooler lines are twisted to correct customer concerns of Harsh Shift, Shudder, Surge, Stall, Transmission Overheating and/or High Transmission Fluid Temperature.
PIE0824A2025-09-10. Service bulletin. This engineering information (EI) closure ends the need for gathering further information from field in regard to fluid leaking at the output seal and/or leaking at the front slip yoke (welch plug leak).
PIE0814B2025-09-10. Service bulletin. This engineering information (EI) closure ends the need for requesting further information from technicians in regard to the Service AWD Lamp illuminated on Driver Information Center (DIC) and to refer to SI for further diagnosis.