GM bulletin 21-NA-271
What it saysThis bulletin advises the technician of a possible kinked coolant hose that might be causing the customers concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P026A Set. NHTSA’s full summary ↓
GM filed this with NHTSA as a service bulletin dated Aug 2, 2024, received Dec 3, 2022, about the engine — 3 documents under this number. It names 26 model years across Chevrolet, GMC and Cadillac (2020–2024). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
One page for every brand it was filed under. Each brand’s bulletins: Chevrolet · GMC · Cadillac.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis bulletin advises the technician of a possible kinked coolant hose that might be causing the customers concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P026A Set.
Trouble codes it names: P026A
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 21-NA-271 | Service bulletin | Aug 2, 2024 | 11006647 | PDF, 187 KB |
| 21-NA-271 | Service bulletin | Aug 1, 2023 | 10241858 | PDF, 1,430 KB |
| 21-NA-271 | Service bulletin | Nov 9, 2022 | 10227054 | not found |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. 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. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themChevrolet 13 model years
GMC 9 model years
Cadillac 4 model years
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 26 model years this bulletin names have filed 9,300 complaints with NHTSA since 2015. 6,429 of them name Engine, Electrical System — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
On the 2021 Chevrolet Silverado, the 108 owners who gave an odometer reading for Engine reported it at a median of 65,000 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
The contact owns a 2024 GMC Yukon XL. The contact received notification of NHTSA Campaign Number: 25V274000 ENGINE AND ENGINE COOLING); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair.
2024 GMC Yukon · Engine · filed with NHTSA Jun 18, 2025 · ODI 11667685
on Sunday I was driving Longisland’ highway around 70 mile per a hour on left line my Cadillac engine stop end notification start engine I barely stop my car called police officer he help me because car it wast safe area with tow truck take my car now car in service almost week still no response and I have a appointment last Saturday…
2022 Cadillac Escalade · Engine · filed with NHTSA May 5, 2025 · ODI 11658942
While driving on the highway my truck started to buck and had a loud engine knocking noise. Speed was greatly reduced so much so that I was going under 45 mph in a posted 65. The check engine light did not come on. While sitting on the side of the highway there was a severe engine knock only when the revs on the engine were increased.
2021 GMC Sierra · Engine · filed with NHTSA Sep 9, 2021 · ODI 11432369
In depth: 2024 Cadillac Escalade engine problems → · 2023 Cadillac Escalade engine problems → · 2022 Cadillac Escalade engine problems → · 2021 Cadillac Escalade engine problems →
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the engine
Source: same model, same component group175 other manufacturer communications filed against these GM models under the same component group (engine), newest first. The eight newest are listed; the rest are on the Chevrolet list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| N262576260 | Service campaign | Oct 15, 2026 | General Motors has decided to conduct a Voluntary Emission Recall. Certain vehicles may have a condition that could cause a small exhaust le… |
| N262568830 | Service campaign | Aug 4, 2026 | Certain vehicles listed above may have a condition in which the oil filter was not adequately tightened. Dealers are to check and tighten th… |
| N262552620 | Service campaign | May 11, 2026 | Certain vehicles may have a condition that could cause the cylinder 2 glow plug to fail. If this failure occurs, the Malfunction Indicator… |
| N262548050 | Service campaign | Apr 24, 2026 | Certain vehicles, may have a condition that could cause the Catalytic Converter to fail. If this failure occurs, the Malfunction Indicator L… |
| N252494003-02 | Service campaign | Jan 21, 2026 | Certain vehicles listed above, may have a condition where the connecting rod and/or crankshaft engine components in these vehicles may have… |
| 25-NA-339 | Service bulletin | Nov 6, 2025 | Under Field Actions N252494000, N252494001, the service procedure includes performing a PICO test on vehicle engines within the identified s… |
| N252508341 | Service campaign | Sep 16, 2025 | Certain vehicles listed above, may have a condition that could cause the engine coolant control valve to fail an onboard vehicle diagnostic… |
| N252508340 | Service campaign | Sep 16, 2025 | Certain vehicles may have a condition that could cause the engine coolant control valve to fail. If this condition were to occur, the Malfun… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Chevrolet, GMC and Cadillac, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM 21-NA-271 a recall?
No. A service bulletin 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 21-NA-271 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every GM warranty extension on file lists the ones GM has filed.
Which vehicles does 21-NA-271 cover?
The manufacturer filed it against 26 model years across 3 brands (Chevrolet, GMC and Cadillac): 2024 Cadillac Escalade, 2023 Cadillac Escalade, 2022 Cadillac Escalade, 2021 Cadillac Escalade, 2024 Chevrolet Silverado, 2023 Chevrolet Silverado and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.