# Over\-the\-air update 661.30

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: Over\-the\-air update
- NHTSA id: 11031807
- Published by NHTSA: 2026\-04\-30
- Manufacturer's number: 661.30
- Manufacturer's date: 2026\-04\-14
- Campaign id or software version: 661.30
- NHTSA component: UNKNOWN OR OTHER
- Manufacturer's system: ECM: ECM \(Engine Control Module\)

## NHTSA's summary

• Fixes to help extend coolant valve life through diagnostic changes.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031807-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031807-9999.pdf)

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

## Vehicles listed

- 2023 CHEVROLET SILVERADO 1500
- 2023 GMC SIERRA 1500

JSON: [/v1/bulletins/11031807](/v1/bulletins/11031807)

[Report an error on this page](https://github.com/wenmar-pro/wenmar-open/issues/new?template=data_correction.yml&title=Data%20correction%3A%20Over-the-air%20update%20661.30&page=https%3A%2F%2Fopen.wenmarpro.com%2Fbulletins%2F11031807&vehicle=Over-the-air%20update%20661.30)