Product Description
CUMMINS 3910810 OEM EXHAUST ROCKER ARM (ROCKER LEVER) – 5.9L 12V (1989–1998)
The Cummins 3910810 OEM exhaust rocker arm (rocker lever) is the factory-correct exhaust rocker for 1989–1998 Dodge Ram 2500/3500 trucks with the 5.9L 12-valve Cummins 6BT. This genuine Cummins lever restores precise valve motion, consistent lash, and long-term durability in high-heat diesel valvetrain environments.
Whether you are refreshing a tired 12-valve, repairing a wiped cam/rocker, or building a reliable tow rig, using genuine Cummins 3910810 hardware ensures OE geometry, metallurgy, and oiling clearances designed for the legendary 5.9L B-series.
Key Features & Benefits
- Genuine Cummins part #3910810 – correct exhaust rocker lever for 5.9L 12-valve B-series applications.
- Matched to OE cam profile for accurate valve lift and timing on the exhaust side.
- Hardened contact surfaces at the valve tip and crosshead for long life under high spring loads.
- Designed for Euro 2 / automotive 5.9L B engines and 12V Dodge Ram 5.9L applications.
- Drop-in replacement – no modifications required when installed with OEM shaft, bolts, and adjusters.
- Ideal for stock and mild performance builds where OE reliability is the priority.
Fitment
Primary automotive fitment (on-road):
- 1989–1993 Dodge D250 / D350 / W250 / W350 with 5.9L 12-valve Cummins (6BT).
- 1994–1998 Dodge Ram 2500 / 3500 with 5.9L 12-valve Cummins (6BT).
Engine platform coverage (B-series diesel):
- Cummins 6BT 5.9L (12-valve B-series automotive & industrial applications).
- Commonly used across select B-series 4B / 4BT / 4BTA 3.9L and 6BT 5.9L engines in off-highway, construction, and industrial equipment (verify by ESN).
Important: Always confirm fitment by engine serial number (ESN) or existing part number before ordering for off-highway/industrial equipment.
Cross-Reference & Related Cummins Valvetrain Parts
Pair this 3910810 exhaust rocker arm with other genuine Cummins valvetrain components for a complete, OE-quality 12-valve refresh:
- CUMMINS 3922488 OEM ROCKER LEVER SHAFT – 5.9L 12V (1989–1998) – supports all intake and exhaust rockers on the 12V 6BT shaft.
- CUMMINS 3910811 OEM INTAKE ROCKER LEVER (ROCKER ARM) – 5.9L 12-VALVE (1989–1998) (intake-side counterpart – use one per intake valve).
- CUMMINS 3937438 OEM ROCKER LEVER ADJUSTING SCREW (VALVE LASH ADJUSTER) – 5.9L 12-VALVE (1989–1998) (replace when threads or tips show wear).
- CUMMINS 3920781 OEM ROCKER ARM BOLT (ROCKER LEVER) – 5.9L 6BT (1989–1998) (securely clamps each rocker to the shaft; replace any stretched or corroded fasteners).
For full top-end service, inspect/replace the following as needed: intake and exhaust valves, valve springs, valve stem guides, and seats on your 5.9L 12-valve cylinder head.
Installation Notes
- Work on a cool engine and follow Cummins service manual procedures.
- Mark or document original rocker positions if reusing any components.
- Inspect rocker shaft journals and oil feed holes; clean or replace as necessary.
- Torque rocker arm bolts in sequence and to the correct spec for your 5.9L 12V application.
- After installation, set valve lash to factory specifications (hot or cold, per Cummins manual).
- Crank engine by hand at least two full revolutions and re-check lash/torque before startup.
Why Buy Genuine Cummins 3910810 from CPP Diesel?
- Genuine Cummins component – no guessing on metallurgy, geometry, or long-term durability.
- Specialized in B-series/ISB diesel – we stock complementary parts for full top-end rebuilds.
- Fast shipping and diesel-focused support for 5.9L and 6.7L Cummins platforms.
- Ideal for stock, tow, and work trucks where uptime and reliability matter most.
Specifications for cummins 3910810
| Parameter | Value |
|---|---|
| Brand | Cummins |
| Part Number | 3910810 |
| Component | Exhaust rocker arm / rocker lever |
| Engine Platform | Cummins B-series, primarily 5.9L 12-valve (6BT) |
| Primary Vehicle Fitment | 1989–1998 Dodge Ram 2500/3500 with 5.9L 12V Cummins (automotive B-series) |
| UPC | Not published by Cummins |
| GTIN | Not published by Cummins |
| Cross Reference | Cummins 3910810 (supersession), related exhaust rocker applications for B-series 5.9L. Some catalogs also reference earlier engineering numbers in the same family; always verify by ESN. |
| E-Codes / Emissions Notes | Used on Euro 2 / automotive 5.9L B engines and equivalent 12-valve 6BT applications where 3910810 is specified. |
| Typical Shipping Weight | Approx. 0.25–0.35 lb (single rocker lever, boxed) |
| Shipping Info | Ships from CPP Diesel via standard ground service; expedited options available at checkout. |
| Country of Origin | As supplied by Cummins (varies by batch; see product packaging for exact origin). |
| Prop 65 Warning | This product may expose you to chemicals, including diesel engine exhaust and other substances, known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov . |
FAQ
Is this the intake or exhaust rocker arm?
This part number 3910810 is the exhaust rocker arm (rocker lever) for the 5.9L 12-valve Cummins. The intake rocker uses a different Cummins part number (commonly 3910811). Always match intake vs exhaust rockers correctly when ordering.
How many exhaust rockers do I need for a 5.9L 12-valve Cummins?
The 6BT 5.9L 12-valve uses six exhaust rockers and six intake rockers – one intake and one exhaust per cylinder. If you are refreshing the entire exhaust side, you will typically order six of part number 3910810.
Should I replace the rocker lever shaft and bolts at the same time?
It is highly recommended to inspect the rocker shaft and rocker bolts when replacing any rockers. A worn shaft or stretched bolts can cause noise, lash variation, and premature rocker wear. Many builders replace the shaft (3922488) and rocker bolts when installing new rockers, especially on high-mileage engines.
Do these rockers come with adjusting screws and lock nuts?
No. The 3910810 rocker lever is sold bare. Reuse your existing adjuster hardware if it is in good condition, or replace with new Cummins adjusting screws and lock nuts. Damaged or mushroomed adjuster tips should always be replaced.
Can I use this rocker arm on industrial or off-highway B-series engines?
This rocker lever is installed on many B-series industrial and off-highway engines, but not all of them. Cummins uses multiple valvetrain combinations across equipment manufacturers. For industrial, agricultural, or construction equipment, always confirm fitment by engine serial number (ESN) or existing part number before ordering.
Is this rocker arm compatible with aftermarket performance cams or heavy-duty valve springs?
Genuine Cummins rockers work well with many mild performance upgrades, but extreme spring pressures and aggressive cam profiles may require aftermarket performance valvetrain components. If you are running high spring pressure, big RPM, or competition use, consult with your camshaft manufacturer and consider upgraded rockers and hardware.
