Warranty extension 114236
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 | Warranty extension |
|---|---|
| NHTSA id | 11036774 |
| Published by NHTSA | 2026-09-03 |
| Manufacturer's number | 114236 |
| Manufacturer's date | 2026-08-24 |
| NHTSA component | ENGINE |
NHTSA's summary
Dealer Incentive for the Completion of Customer Satisfaction Notice (CSN) 66D
The document
The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.
Components
Engine
| JEEP GRAND CHEROKEE | 2026, 2027 |
|---|---|
| JEEP GRAND CHEROKEE L | 2026, 2027 |
Listing a model year does not mean every vehicle of it is concerned: the document says which.
| 66D Combo Rev2 | 2026-10-16. Service campaign. Revised Customer Satisfaction Notification 66D – Spark Plugs - Dealer Notification |
|---|---|
| 66D Combo Rev2 | 2026-10-16. Service campaign. Revised Customer Satisfaction Notification 66D – Spark Plugs - Dealer Notification |
| 09-013-26 REV. A | 2026-10-07. Service bulletin. Engine Runs Rough Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0300-00 - Random/Multiple Cylinder Misfire Detected. ● P0301-00 - Cylinder 1 Misfire. ● P0302-00 - Cylinder 2 Misfire. ● P0303-00 - Cylinder 3 Misfire. ● P0304-00 - Cylinder 4 Misfire. Customers may also comment on the following: ● Engine runs rough. This bulletin involves replacing all four main chamber spark plugs. |
| 09-023-26 | 2026-09-30. Service bulletin. Umbrella Valve Seal Missing From Cylinder Head Cover Vehicle may exhibit a MIL-ON. SYMPTOM: Upon inspection the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have set: ● P0300-00 - Random/Multiple Cylinder Misfire Detected. ● P0301-00 - Cylinder 1 Misfire. ● P0302-00 - Cylinder 2 Misfire. ● P0303-00 - Cylinder 3 Misfire. ● P0304-00 - Cylinder 4 Misfire. This bulletin involves inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover. |
| 66D Combo Rev1 | 2026-09-03. Warranty extension. CUSTOMER SATISFACTION NOTIFICATION NORTH AMERICA Spark Plugs Reference: 66D The spark plugs insulator on approximately 48,000 of the above vehicles may break due to excessive cylinder pressure. This pressure can cause the spark plug's ceramic insulator to crack, leading to a rough-running engine. If this issue is not resolved promptly, the broken fragments can fall into the cylinder and cause internal engine damage. |
| 114273 | 2026-09-03. Warranty extension. D-26-18 Rev. A Dealer Incentive for the Completion of Customer Satisfaction Notification 66D |
| 114275 | 2026-09-03. Warranty extension. ID-26-38 Rev. A Dealer Incentive for the Completion of Customer Satisfaction Notification 66D |
| 114238 | 2026-09-03. Warranty extension. Dealer Incentive for the Completion of Customer Satisfaction Notice (CSN) 66D |
| S2618000003 REV.G | 2026-08-26. Service bulletin. MIL-On, Engine Runs Rough |
| 09-020-26 | 2026-08-26. Service bulletin. Umbrella Valve Seal Missing From Cylinder Vehicle may exhibit a MIL-ON. SYMPTOM: Upon inspection the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have set: ● P0300-00 - Random/Multiple Cylinder Misfire Detected. ● P0301-00 - Cylinder 1 Misfire. ● P0302-00 - Cylinder 2 Misfire. ● P0303-00 - Cylinder 3 Misfire. ● P0304-00 - Cylinder 4 Misfire. This bulletin involves inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover. |