Chevrolet bulletin 663.20
Chevrolet filed this with NHTSA as a over-the-air update dated Aug 27, 2026, received Jul 29, 2026, about the unknown or other — 5 documents under this number. It names 7 model years (2024–2026). A over-the-air update is not a safety recall — there is no NHTSA campaign number and no federal requirement — but it is usually work the manufacturer pays for on the vehicles it names; the dealer checks the VIN against the manufacturer’s list.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communication• Improvements to start reliability and reduced check engine light activation • Improvements to turbo system diagnostics • Improvements to active cabin ventilation • Additional protection for the health of your battery • Updates to help prevent excessive battery drain and overheating • Improvements to the software update system
Documents filed under this number
| Document | Kind | Dated | NHTSA id |
|---|---|---|---|
| 663.20 | Over-the-air update | Aug 27, 2026 | 11036469 |
| 663.20 | Over-the-air update | Aug 24, 2026 | 11036478 |
| 663.20 | Over-the-air update | Jul 31, 2026 | 11035441 |
| 663.20 | Over-the-air update | Jul 31, 2026 | 11035440 |
| 663.20 | Over-the-air update | Jul 16, 2026 | 11035293 |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5; the full text comes from the manufacturer or a dealer. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. Quote it at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
Common questions
Source: NHTSA, 49 CFR 579.5Is Chevrolet 663.20 a recall?
No. A over-the-air update is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the 663.20 repair free?
A over-the-air update is usually paid by the manufacturer on the vehicles it names, within the terms and time limit the document sets; the dealer checks the VIN against the manufacturer’s list.
Which vehicles does 663.20 cover?
The manufacturer filed it against 7 model years: 2025 Chevrolet Colorado, 2024 Chevrolet Colorado, 2026 Chevrolet Silverado, 2026 Chevrolet Suburban, 2025 Chevrolet Suburban, 2026 Chevrolet Tahoe and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.