Product Description
Cummins 3901306 — Genuine Camshaft Bushing for 5.9L (B-Series)
MPN: 3901306 | Also Known As: cam bushing, camshaft bearing (front position) | Position: Front cam bushing (see specs)
Genuine Cummins camshaft bushing engineered for precise cam support and oil control on early B-Series applications. Direct-fit for 1989–1997 5.9L 12-valve Dodge Ram. Sold individually (1 per engine).
Features & Benefits
- OE geometry for proper cam alignment and oiling.
- Direct-fit replacement in the front position of B-Series blocks.
- Stabilizes camshaft to help maintain timing and reduce wear.
- Built to Cummins standards for durability and service life.
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1989–1993 | 5.9L 12V (6BT) | Ram 2500/3500 |
| 1994–1997 | 5.9L 12V (6BT) | Ram 2500/3500 |
Industrial/Off-Highway: B-Series 4B/6B front position through approx. up to 5/1997; verify by ESN before ordering.
Compatibility Notes:
- 3901306 covers early B-Series/12-valve through ~5/1997 (front position).
- For 1997.5–2018 5.9L/6.7L “storm block” & common-rail engines, Cummins uses the thicker bushing 3940059—order that part instead for late 12V, 24V VP44, and 6.7L applications.
Specifications
- Type: Camshaft bushing (front position)
- OE Part Number: 3901306
- Outside Diameter: 2.25 in (front position up to 5/1997)
- Quantity Required: 1 per engine (sold individually)
Often Paired With
- Camshaft gear: 3929028
- Camshaft key: 3902332
- Cam thrust plate/retainer: 3927155
- Thick cam bushing (late blocks): 3940059 (for 1997.5–2018)
What’s In The Box
- (1) Genuine Cummins Camshaft Bushing (3901306)
Installation Tips
- Clean and inspect cam bore; measure to confirm proper interference.
- Align the lubrication feed hole; press with the correct driver.
- Verify cam end-play and thrust plate torque per factory spec.
- Use assembly lube; rotate by hand to confirm free movement.
FAQ
WILL THIS FIT MY 1989–1997 5.9L 12-VALVE CUMMINS?
Yes—3901306 is the OE front cam bushing used on early 5.9L 12-valve applications (approx. up to 5/1997). Confirm by VIN/ESN.
HOW MANY BUSHINGS DOES MY ENGINE USE?
One front cam bushing. The remaining journals ride directly in the block on these engines.
WHAT’S THE DIFFERENCE BETWEEN 3901306 AND 3940059?
3940059 is a thicker cam bushing used on late 12V (1997.5-up), 24V VP44, and 6.7L engines (“storm block” and later). Use 3940059 for those applications.
DO I NEED SPECIAL TOOLS?
A proper bushing driver/installer is recommended to press the bushing squarely and align the oil hole; avoid improvised tools that may distort the bore.
IS THIS A GENUINE CUMMINS PART?
Yes—OE Cummins 3901306.
