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Service bulletins for the 2026 Jeep Grand Cherokee

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.

274 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
66D Combo Rev22026-10-16. Service campaign. ENGINE. Revised Customer Satisfaction Notification 66D – Spark Plugs - Dealer Notification
66D Combo Rev22026-10-16. Service campaign. ENGINE. Revised Customer Satisfaction Notification 66D – Spark Plugs - Dealer Notification
09-013-26 REV. A2026-10-07. Service bulletin. ENGINE. 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.
09-023-262026-09-30. Service bulletin. ENGINE. 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 Rev12026-09-03. Warranty extension. ENGINE. 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.
1142732026-09-03. Warranty extension. ENGINE. D-26-18 Rev. A Dealer Incentive for the Completion of Customer Satisfaction Notification 66D
1142752026-09-03. Warranty extension. ENGINE. ID-26-38 Rev. A Dealer Incentive for the Completion of Customer Satisfaction Notification 66D
1142382026-09-03. Warranty extension. ENGINE. Dealer Incentive for the Completion of Customer Satisfaction Notice (CSN) 66D
1142362026-09-03. Warranty extension. ENGINE. Dealer Incentive for the Completion of Customer Satisfaction Notice (CSN) 66D
S2618000003 REV.G2026-08-26. Service bulletin. ENGINE. MIL-On, Engine Runs Rough
09-020-262026-08-26. Service bulletin. ENGINE. 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.
09-017-26 REV. A2026-08-26. Service bulletin. ENGINE. Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. 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. 2. Engine oil level is low. IMPORTANT! If none of above symptoms are present, this TSB does NOT apply. This bulletin involves inspecting the engine oil level, possibly inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover.
S2618000003 REV.F2026-08-19. Service bulletin. ENGINE. MIL-On, Engine Runs Rough
1138352026-08-13. Service bulletin. ENGINE. COVER - CYLINDER HEAD
09-019-262026-08-13. Service bulletin. ENGINE. Potential Engine Oil Overfill Customers may comment on the following: SYMPTOM: ● Misfires or sluggish engine performance. This bulletin involves inspecting the engine oil level and possibly performing an engine oil change.
09-017-262026-08-13. Service bulletin. ENGINE. Umbrella Valve Seal Missing From Cylinder Head Cover Customer may experience a MIL-ON and/or an indication of low engine oil level. SYMPTOM: Upon inspection the technician may find the following: 1. 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. 2. Engine oil level is low. IMPORTANT! If none of above symptoms are present, this TSB does NOT apply. This bulletin involves inspecting the engine oil level, possibly inspecting for a missing umbrella valve seal on the underside of the cylinder head cover and, if necessary, replacing the cylinder head cover
66D Dealer2026-07-29. Service campaign. ENGINE. Spark Plugs 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.
09-014-262026-07-23. Service bulletin. FUEL/PROPULSION SYSTEM; ENGINE. Not applicable to vehicles built for US market. Engine Runs Rough Customers may comment on the following: SYMPTOM: ● Engine runs rough. This bulletin involves filling the fuel tank with premium fuel (95 RON minimum) during the Pre-Delivery Inspection PDI process.
S2618000003 REV.E2026-07-18. Service bulletin. ENGINE. MIL-On, Engine Runs Rough
1132412026-07-18. Service bulletin. ENGINE. SPARK PLUG - NONE
1132402026-07-18. Service bulletin. ENGINE. SPARK PLUG - NONE
09-013-262026-07-18. Service bulletin. ENGINE. 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.
1126392026-07-08. Service bulletin. ENGINE. THROTTLE BODY – NONE
1126402026-07-08. Service bulletin. ENGINE. THROTTLE BODY – NONE
1128422026-07-02. Service bulletin. ENGINE. BOLT - HEX FLANGE HEAD

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.