TSB N252508350 — Chevrolet and GMC Service campaign

N252508350 is a service campaign on file with NHTSA for 2 Chevrolet and GMC models, 2021 model years. A TSB is factory repair guidance, not a recall — the repair is not automatically free.

What the bulletin says. Certain vehicles listed above, may have a condition that could cause the engine coolant thermostat to open at a lower temperature than intended. If this condition were to occur, the Malfunction Indicator Lamp (Check Engine Light) will illuminate and a diagnostic trouble code…

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

1Document filed
2Vehicles named
1Model year

Worth checking your VIN against. N252508350 is filed as a service campaign, which unlike an ordinary bulletin can mean free or reimbursed work when a vehicle qualifies. Ask a dealer using the document ID below, and check open recalls separately at nhtsa.gov/recalls.

Vehicles and model years N252508350 names

VehicleModel years
Chevrolet Blazer 2021
GMC Acadia 2021

Every document filed under N252508350

Document IDFiledType
N252508350 October 21, 2025 Service campaign

What N252508350 covers

Engine — the component vocabulary NHTSA files this communication under.

← All Chevrolet Blazer TSB years TSB lookup by model

Questions buyers ask

What is TSB N252508350?

N252508350 is a service campaign filed with NHTSA by Chevrolet and GMC, covering 2 Chevrolet and GMC models across the 2021 model years. NHTSA's summary reads: Certain vehicles listed above, may have a condition that could cause the engine coolant thermostat to open at a lower temperature than intended. If this condition were to occur, the Malfunction Indicator Lamp (Check Engine Light) will illuminate and a diagnostic trouble code…

Which vehicles does N252508350 cover?

NHTSA's file names Chevrolet Blazer (2021); GMC Acadia (2021). 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 N252508350 a recall, and is the repair free?

N252508350 is filed as a service campaign, not a recall — but this is the kind of communication that can mean free or reimbursed work if your VIN qualifies. Take the number to a dealer and ask. Recalls are separate and always free; check yours by VIN at nhtsa.gov/recalls.

How do I get the full text of N252508350?

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 N252508350, 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 N252508350. Check any specific vehicle's open recalls by VIN at nhtsa.gov/recalls.