Product Description
Cummins 4089263 OEM Upper Engine Gasket Set – ISB 5.9L (2003–2007) Rear Gear
The Cummins 4089263 OEM Upper Engine Gasket Set is the genuine factory sealing kit designed for 2003–2007 ISB 5.9L Common Rail Cummins engines equipped with the rear gear train configuration. This complete upper engine gasket set includes the critical gaskets, seals, and sealing components required for cylinder head service, injector replacement, valve train repairs, top-end rebuilds, and upper engine resealing procedures. Built to Cummins OEM specifications, the 4089263 gasket set delivers long-lasting durability, proper sealing performance, and leak-free operation in demanding diesel applications.
Whether you're repairing coolant leaks, replacing injector seals, performing a head gasket service, or refreshing a high-mileage 5.9L Common Rail Cummins engine, the genuine Cummins 4089263 gasket set provides the quality, fitment, and reliability required to restore factory sealing performance. Designed specifically for rear gear train ISB engines, this kit is trusted by professional diesel technicians, engine builders, and fleet maintenance departments.
Features
- Genuine Cummins OEM upper engine gasket set
- Designed for 2003–2007 ISB 5.9L Common Rail engines
- Correct configuration for rear gear train applications
- Ideal for cylinder head service and top-end rebuilds
- Includes critical upper engine sealing components
- OEM-quality materials for leak-free performance
- Built to withstand heat, pressure, and thermal cycling
- Excellent for injector service and valve train repairs
- Factory-correct fit and sealing performance
- Trusted by diesel repair professionals and engine builders
Fitment
- 2003–2007 Dodge Ram 2500 5.9L Cummins Common Rail
- 2003–2007 Dodge Ram 3500 5.9L Cummins Common Rail
- Cummins ISB 5.9L Rear Gear Engines
- Select Cummins QSB 5.9L Applications
- Industrial and commercial rear-gear ISB platforms
- Rear gear train engine configurations only
Note: Verify engine serial number (ESN) before ordering. This gasket set is designed specifically for rear gear train ISB/QSB applications and may not fit all 5.9L Cummins engine configurations.
What's Included
- Cummins 4089263 OEM Upper Engine Gasket Set
- Cylinder head sealing components
- Valve cover and rocker housing gaskets
- Intake and exhaust manifold gaskets
- Injector sealing components
- O-rings, seals, and upper engine service gaskets
- Additional upper-end sealing components as specified by ESN
Specifications
- Manufacturer: Cummins Genuine Parts
- Part Number: 4089263
- Product Type: Upper Engine Gasket Set
- Engine Family: ISB / QSB
- Engine Displacement: 5.9L
- Engine Configuration: Rear Gear Train
- Fuel System: Common Rail
- Application Years: 2003–2007
- OEM Quality: Genuine Cummins Factory Component
- Material: OEM Heat and Pressure Resistant Gasket Materials
- Primary Use: Cylinder Head Service and Upper Engine Rebuilds
- Compatibility: ISB and Select QSB Engines
- ESN Verification: Recommended Before Ordering
Cross Reference Numbers
4089263, DS-4089263, Cummins 4089263, ISB Upper Gasket Set, QSB Upper Gasket Set, Cummins 5.9L Upper Engine Gasket Kit, 3900267, 3900625, 3903924
FAQ
What is included in the Cummins 4089263 upper engine gasket set?
The kit typically includes upper-engine sealing components such as cylinder head gaskets, valve cover gaskets, intake and exhaust manifold gaskets, injector seals, O-rings, and related sealing components. Exact contents may vary by engine serial number.
Will this fit all 5.9L Cummins engines?
No. The 4089263 gasket set is designed for rear gear train ISB and select QSB 5.9L engines. Verification by engine serial number is strongly recommended before purchase.
Does this gasket set include a head gasket?
Contents can vary by engine serial number and application. Always verify kit contents if a specific head gasket configuration is required for your repair.
Is this an OEM Cummins gasket set?
Yes. Part number 4089263 is a genuine Cummins OEM upper engine gasket kit manufactured to factory specifications for proper fitment and long-term sealing performance.
Can this be used for injector replacement and top-end repairs?
Yes. This gasket set is commonly used during injector replacement, cylinder head service, valve train repairs, and complete upper-engine resealing procedures.
Why should I verify my engine serial number?
Cummins produced multiple ISB and QSB engine configurations. Verifying the ESN ensures you receive the correct gasket set for your engine's gear train and component configuration.
