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Service bulletin 18NA026

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 id10171885
Published by NHTSA2020-03-02
Manufacturer's number18NA026
Manufacturer's date2020-01-22
NHTSA componentFUEL SYSTEM, GASOLINE; POWER TRAIN; EQUIPMENT ADAPTIVE/MOBILITY

NHTSA's summary

This technical bulletin provides a procedure to install an oil cooler line fitting seal, including applying medium strength threadlocker (blue) to the retaining bolt to stop transmission fluid leaking from the transmission oil cooler line retaining bolt passage.

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

Equipment and accessories, Fuel system, Transmission and driveline

Vehicles listed
CADILLAC ESCALADE2018
CADILLAC ESCALADE ESV2018
CHEVROLET CAMARO2017, 2018
CHEVROLET SILVERADO 15002019 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET TAHOE2018
GMC SIERRA 15002019 (the catalog's model; the bulletin names a series or trim of it)
GMC YUKON2018
GMC YUKON XL2018

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

Recalls for the same vehicles and component
26V2890002026-05-07. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)
23V0470002023-02-02. FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY
20221602022-03-31. Accessories
21V4960002021-07-01. EQUIPMENT:ELECTRICAL:ENGINE BLOCK HEATER
20205052020-10-23. Powertrain
20V6500002020-10-22. POWER TRAIN:DRIVELINE:DRIVESHAFT
20201652020-04-16. Accessories
20194942019-10-03. Accessories
20192052019-04-26. Accessories

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
PI0281L2025-06-12. Service bulletin. This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
23-NA-1852025-04-28. Service bulletin. This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting Concerns.
25-NA-0652025-04-24. Service bulletin. This informational bulletin instructs the tech when fuel/fluid is needed to be tested and where it can be sent for analysis.
PIP5966A2025-03-02. Service bulletin. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
PIP5966A2025-03-02. Service bulletin. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
16-NA-0192025-02-19. Service bulletin. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP5175F2025-02-10. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
09-06-04-026Z2025-01-23. Service bulletin. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
PIC6454A2025-01-20. Service bulletin. This Preliminary Information communicates additional information to the customer on the "No Lift Shift" feature found on all Manual Transmission equipped Camaros.
08-07-30-035I2024-12-19. Service bulletin. This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.