Special Coverage N262552620: Glow Plug — Cylinder 2 (3.0L Duramax SUVs)

Special Coverage N262552620 extends warranty coverage on the cylinder 2 glow plug for certain 2021 full-size GM SUVs — Cadillac Escalade and Escalade ESV, Chevrolet Tahoe and Suburban, GMC Yukon and Yukon XL. Coverage runs 15 years or 150,000 miles from the original in-service date, whichever comes first, and it applies regardless of ownership. This is not a recall. It is GM agreeing to pay for a known failure long after the normal warranty has expired — and the qualifying codes are P0672, P1339 and P06C6.

Read the primary document yourself: GM Special Coverage bulletin N262552620, released 11 May 2026 (PDF), hosted by NHTSA as a manufacturer communication. Read in full.

What a Special Coverage Actually Is

Worth being clear about, because it is neither a recall nor ordinary warranty and people miss out by not understanding the difference.

A Special Coverage is a warranty extension. GM identifies a component with a higher-than-expected failure rate, decides the original warranty term was not long enough, and extends coverage on that specific part for a longer period.

	Safety recall	Special Coverage
Filed with NHTSA as a campaign	Yes	No
Shows in NHTSA VIN lookup	Yes	No
Bulletin published by NHTSA	Yes — Part 573 report	Yes — as a manufacturer communication
Owner letter	Yes	Yes, for this programme
Repair performed proactively	Yes	No — only if the part fails
Cost to owner	None	None, if it qualifies

Read the fifth row carefully, because it is the whole character of this programme. Nobody is going to fix your glow plug pre-emptively. The coverage only does anything if the part actually fails — at which point it pays for the repair you would otherwise have funded yourself.

And read the second row, because it is how owners lose money. A Special Coverage does not appear in a NHTSA VIN lookup. If you take a 2021 Duramax SUV to an independent shop with a check engine light, get a diagnosis of a failed glow plug, and pay for it — you have paid for something GM would have covered.

Note the third row, though. The bulletin itself is a public document — NHTSA publishes manufacturer communications alongside recall filings, which is how the PDF linked at the top of this page is available. What is not public is whether your VIN is on the list. That takes a dealer.

The Three Codes That Qualify

This is the most practically useful detail in the bulletin, and it is unusually specific. GM's service procedure states that a vehicle may come in with conditions leading to a cylinder 2 glow plug diagnosis, and that these may include, but are not limited to:

• P0672 — glow plug circuit, cylinder 2
• P1339
• P06C6

Note the "not limited to." Those three are named, but GM does not present them as an exhaustive list — so a different code does not automatically rule you out.

If you have a check engine light on a 2021 Duramax SUV, those are the numbers to look for. Pull the codes before you authorise any work — our guide to reading GM trouble codes covers how, and any parts store will read them free.

Note also what glow plugs do, since it explains the symptom pattern. A diesel has no spark plugs; it ignites fuel by compression heat alone. Glow plugs are electric heating elements that warm the combustion chamber so a cold engine will start and run cleanly. Which is why glow plug faults show up as cold-start problems — hard starting, rough running and white smoke when cold, clearing as the engine warms. A vehicle that runs perfectly once warm can still have a dead glow plug. That explanation is general diesel knowledge, not from the bulletin, which describes only the check engine light and stored code.

The Gate — and What It Still Pays

This is the condition that determines whether the coverage pays, and it is narrower than owners expect — but not as harsh as it first looks.

GM's bulletin permits the repair only if diagnosis actually leads to replacement of the number 2 glow plug. If it does not, GM's instruction to the dealer is specific:

Inform the customer that the diagnosis up to this point will be covered, but any other diagnosis or repair work must be paid by the customer or a policy adjustment.

That matters, and an earlier version of this page understated it. You are not gambling a diagnostic fee on whether the answer comes back in your favour. GM pays for the investigation either way — there is a dedicated diagnostic-only labour operation for exactly that outcome. What you pay for is any further work once the answer turns out to be something else.

Two consequences still follow.

It covers one glow plug, not the set. If diagnosis points to cylinder 5, this programme does not pay for it.

It does not become a general diesel repair fund. A no-start with a completely different root cause is not covered simply because the vehicle is in the population.

There is also a warranty-routing detail worth knowing. GM instructs that vehicles still within applicable warranty coverage for the component should be repaired under the regular warranty operation — base, powertrain or emissions — and that only vehicles outside that warranty use the special coverage labour operation. Either way it is free to you; it only changes which pot the dealer bills.

Why Cylinder 2

An obvious question, and worth addressing honestly.

GM's bulletin names cylinder 2 specifically rather than glow plugs generally, which tells you the failure is concentrated at that position rather than spread evenly across the engine.

The bulletin does not state a root cause, and we are not going to invent one. Unlike a Part 573 recall report, a special coverage bulletin carries no regulatory obligation to explain why something fails — it describes the condition, the fix and the terms, and stops.

One detail in the parts list is suggestive. GM lists a throttle body gasket alongside the glow plug, which implies the throttle body has to come off to reach cylinder 2 on this engine. That is our reading of the parts list, not something GM states.

What Is Covered and for How Long

15 years or 150,000 miles (240,000 km) from the original in-service date, whichever comes first.

That is a genuinely long extension. On a 2021 vehicle it runs into the mid-2030s, well beyond any powertrain warranty these SUVs carried.

And it applies regardless of ownership. That phrase matters more than it looks:

• You do not have to be the original owner. Buy one of these used and the coverage comes with the vehicle.
• You do not need to have serviced it at a dealer for the coverage to exist.
• It follows the VIN, not the person.

Which makes this worth knowing if you are shopping for a used 2021 Duramax SUV — a known failure point with a decade of remaining manufacturer coverage on it is a materially different proposition from an uncovered one.

On vehicle service contracts: eligible claims with repair orders dated on or after 11 May 2026 go under this special coverage and must use the bulletin's labour operation codes. Repair orders before that date must be submitted to the service contract provider instead.

And a clause worth reading if you hold a third-party warranty. GM states the right to reimbursement is personal to the owner or lessee, may not be assigned, and confers no rights on third parties including service contract providers — no subrogation, no contribution. Your aftermarket warranty company cannot pay the claim and then recover it from GM.

Qualifying repairs are performed at no charge to the customer. Courtesy transportation may be available if you and the vehicle qualify under GM's separate bulletin 07-00-89-037 — worth asking when you book.

Parts and Labour

Qty	Part	Part number
1	Glow Plug	24000504
1	Throttle Body Gasket	55490568

GM's published labour time is 0.6 hours for the cylinder 2 glow plug replacement, plus 0.1 to 1.0 hours of diagnostic time.

That 0.6 figure is worth holding on to. If you are outside coverage and an independent shop quotes several hours for a single glow plug on this engine, GM's own labour guide says it takes about thirty-six minutes once diagnosed.

On parts availability, GM is blunt: supply is limited, quantity limiters may apply, parts may be non-returnable, and dealers are told not to order them as shelf stock because relatively few vehicles are expected to need the fix. A backorder is the system working as designed.

Reimbursement

If you already paid for a cylinder 2 glow plug replacement on one of these vehicles, there is a documented reimbursement process — and a deadline.

GM's bulletin states that requests for reimbursement of previously paid repairs must be submitted to a dealer prior to or by 31 May 2027. That window is open at the time of writing, which is not true of every GM special coverage — the turbocharger programme's reimbursement window, by comparison, closed in February 2026.

What you need:

• The original repair order, showing the glow plug replacement, the date and the mileage.
• Proof of payment. Card statement or receipt.
• Submission through a GM dealer. The bulletin carries dedicated labour operations for both approved and denied claims, so a denial is a documented outcome rather than a brush-off.

GM reimburses reasonable and customary expenses for the repair itself. Independent shop invoices are usually acceptable; cash with no paper trail is a hard sell.

How to Check and What to Say

Because this will not appear in a NHTSA VIN lookup, the route is GM's own systems.

1. Pull the codes first if the light is on. Look for P0672, P1339 or P06C6.
2. Call a GM dealer — Chevrolet, GMC or Cadillac as appropriate — and name the programme: Special Coverage N262552620.
3. Ask them to check the Applicable Warranties section in Investigate Vehicle History. That is where GM says this coverage appears — not the field actions list where recalls sit, which is why asking "do I have any recalls" returns nothing.
4. Describe the symptoms, particularly anything cold-start related.
5. Do not authorise a paid repair on a failed glow plug until this has been checked. That is the entire financial point of the programme.

A Note on Sourcing

We cite documents we have read and label the rest.

This page is now built from the GM Special Coverage bulletin N262552620, released 11 May 2026 and hosted by NHTSA as a manufacturer communication, which we have opened and read in full. That supplies the covered models and model year, the condition, the 15-year / 150,000-mile term, the vehicle service contract cut-off, the anti-assignment clause, the correction, the part numbers, the labour times and operations, the qualifying codes, the diagnostic coverage rule, the parts availability caveats and the reimbursement deadline.

An earlier version of this page was written from secondary reporting and said so. Four things have changed as a result of reading the document: reimbursement terms are now confirmed rather than unknown; GM does send an owner letter, where we had said one would not necessarily arrive; diagnosis is covered even when it does not lead to a covered repair, which we had understated; and we have removed an unverified claim about an earlier bulletin covering 2020 trucks.

The bulletin names no engine. It lists six 2021 SUVs and describes a glow plug condition. Since glow plugs exist only on diesel engines and the sole diesel offered in those vehicles for 2021 was the 3.0L Duramax, the engine scope follows — but that is our inference, not GM's wording. If you have one of these SUVs with a petrol engine, the programme cannot apply to you.

The explanation of what glow plugs do, and the reading of the throttle body gasket as an access clue, are ours and are labelled where they appear.

Your dealer's IVH check is the authority on whether your VIN is included, and the bulletin is the authority on terms.

What Other Pages on This Programme Get Wrong

• Calling it a recall. It is a Special Coverage — a warranty extension. Nothing gets fixed proactively and it does not appear in a NHTSA VIN lookup. Those differences are exactly why owners miss it.
• Saying no document exists. NHTSA publishes GM's manufacturer communications, and this bulletin is public — including the parts list, labour times and reimbursement deadline. We had this wrong on a related page ourselves.
• Not listing the qualifying codes. P0672, P1339 and P06C6 are the practical trigger, and GM notes the list is not exhaustive.
• Missing the reimbursement deadline. 31 May 2027. Owners who already paid have a real window, and it is not open-ended.
• Overstating the gate. Yes, the coverage is limited to the number 2 glow plug — but diagnosis is covered even if the answer turns out to be something else. Owners who think they are risking a diagnostic fee stay away for no reason.
• Missing "regardless of ownership." This follows the VIN, not the original buyer — which makes it directly relevant to anyone shopping a used 2021 Duramax SUV.
• Not explaining the cold-start connection. Glow plugs heat the combustion chamber so a cold diesel starts cleanly. A vehicle that runs fine warm can still have a dead one, and owners dismiss the symptom because it goes away.
• Quoting inflated labour. GM pays 0.6 hours for the replacement.

Frequently Asked Questions

Is this a recall?

No. It is a Special Coverage, which is a warranty extension on one component. Nothing is repaired unless the part actually fails, and it will not show up in a NHTSA VIN lookup. GM does send owner letters for this programme, and the bulletin itself is a public document. It is free when it applies.

Which vehicles does it cover?

Certain 2021 model year full-size GM SUVs — Cadillac Escalade and Escalade ESV, Chevrolet Tahoe and Suburban, GMC Yukon and Yukon XL. Only the 2021 model year. The bulletin names no engine, but since glow plugs are a diesel component, in practice that means the 3.0L Duramax.

How long does the coverage last?

15 years or 150,000 miles from the date the vehicle was originally placed in service, whichever comes first. On a 2021 vehicle that runs into the mid-2030s, and it applies regardless of ownership — so it transfers with the vehicle when it is sold.

What codes should I look for?

P0672, P1339 and P06C6. GM's service procedure names those specifically while noting the list is not exhaustive. If your check engine light is on and you get one of them on a 2021 Duramax SUV, call a dealer and name Special Coverage N262552620 before authorising any paid work.

My glow plug failed but it was a different cylinder.

Then the replacement is not covered — the bulletin is explicit that the repair is permitted only where diagnosis leads to replacing the number 2 glow plug. But note that GM still covers the diagnosis that got you to that answer. Only the further repair work falls to you.

Will I be charged for the diagnosis if it turns out not to be covered?

No. GM's bulletin instructs the dealer to tell you the diagnosis up to that point is covered, and carries a dedicated diagnostic-only labour operation for exactly that case.

What would I actually notice?

Cold-start symptoms, mainly — hard starting, rough running or white smoke when the engine is cold, improving as it warms. Glow plugs exist to heat the combustion chamber so a cold diesel ignites properly, so a failure shows up before the engine is up to temperature. A truck that drives perfectly once warm can still have a dead glow plug and a stored code. The bulletin itself describes only the check engine light and stored code.

I already paid to have this fixed.

You have until 31 May 2027 to claim. Take the original repair order showing the glow plug replacement, the date and the mileage, plus proof of payment, to a GM dealer and reference N262552620.

How long should the repair take?

GM's published labour time is 0.6 hours for the glow plug replacement, plus 0.1 to 1.0 hours for diagnosis. Parts availability is the bigger variable — GM tells dealers not to stock these.

How do I find out if my VIN is included?

Ask a GM dealer to check the Applicable Warranties section of Investigate Vehicle History and name programme N262552620. Because this is not a NHTSA campaign, GM's own warranty system is the only place that will give you a definitive answer on your VIN.

Where can I read the actual bulletin?

It is public. NHTSA hosts GM's manufacturer communications, and bulletin N262552620 contains the covered models, the condition, the coverage term, the parts list, the labour operations, the service procedure and the reimbursement terms.

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Sources

• GM Special Coverage bulletin N262552620 (PDF) — released 11 May 2026, hosted by NHTSA as a manufacturer communication. Primary source for this page; opened and read in full.
• GM bulletin 07-00-89-037 — courtesy transportation eligibility, referenced by the above. Not read directly.

Coverage terms and part numbers can be superseded — always verify eligibility against your specific VIN through a GM dealer, naming programme N262552620 and asking them to check the Applicable Warranties section of Investigate Vehicle History.