TSB A23-078 — Honda Service bulletin

A23-078 is a service bulletin on file with NHTSA for 2 Honda models, 2017–2019 model years, filed and re-filed as 5 documents. A TSB is factory repair guidance, not a recall — the repair is not automatically free.

What the bulletin says. Service Bulletin - Torque converters may not have been manufactured to proper specifications. As a result, the lock-up clutch cannot provide adequate holding force due to pressure bleeding down through a crack in the lock-up piston. The reduced lock-up clutch capacity results in…

NHTSA's own summary of the document, quoted from the public manufacturer-communications file.

5Documents filed
2Vehicles named
3Model years

Vehicles and model years A23-078 names

VehicleModel years
Honda Pilot 2017, 2018, 2019
Honda Ridgeline 2017, 2018, 2019

Every document filed under A23-078

Manufacturers re-issue a bulletin as the repair changes, and file separate copies for technicians and for owners. All of them carry the same number.

Document IDFiledType
A23-078 May 21, 2025 Service bulletin
A23-078 May 21, 2025 Service bulletin
A23-078 April 18, 2025 Service bulletin
A23-078 October 6, 2023 Service bulletin
A23-078 August 31, 2023 Service bulletin

What A23-078 covers

Engine, Transmission & drivetrain — the component vocabulary NHTSA files this communication under.

← All Honda Pilot TSB years TSB lookup by model

Questions buyers ask

What is TSB A23-078?

A23-078 is a service bulletin filed with NHTSA by Honda, covering 2 Honda models across the 2017–2019 model years. NHTSA's summary reads: Service Bulletin - Torque converters may not have been manufactured to proper specifications. As a result, the lock-up clutch cannot provide adequate holding force due to pressure bleeding down through a crack in the lock-up piston. The reduced lock-up clutch capacity results in…

Which vehicles does A23-078 cover?

NHTSA's file names Honda Pilot (2017–2019); Honda Ridgeline (2017–2019). A bulletin number can be re-issued against more vehicles later, so check the model-year list on this page against your own.

Is TSB A23-078 a recall, and is the repair free?

No. A23-078 is repair guidance the manufacturer sent its dealers, not a safety defect finding. You pay for the work unless the vehicle is still under warranty. Recall repairs, by contrast, are always free.

How do I get the full text of A23-078?

Take the document ID to a dealer's service desk, or search NHTSA's manufacturer-communications records. This page carries every document ID filed under A23-078, its date, and NHTSA's own summary from the public file.

Data updated 2026-08-20 from NHTSA's public records

Every number on this page is a count of records in the federal complaint, recall, and investigation files published by NHTSA's Office of Defects Investigation. This page lists only what NHTSA's manufacturer-communications file records under A23-078. Check any specific vehicle's open recalls by VIN at nhtsa.gov/recalls.