Product Description
Cummins 3918999 — Genuine Harmonic Balancer / Tuned Vibration Damper for 5.9L ISB
MPN: 3918999 | Also Known As: harmonic balancer, crankshaft damper, vibration damper (dampener) | Cross-Refs (ID only): 3915069; Komatsu 6735-31-8120
Genuine Cummins tuned vibration damper engineered to control torsional vibrations and protect the crankshaft, bearings, and accessory drive on late 2nd-gen 5.9L ISB platforms. Direct-fit for 1998.5–2002 5.9L (24-valve VP44). Sold individually (1 per engine).
Features & Benefits
- OE-calibrated rubber isolator between inertia ring and hub for precise harmonic control.
- Direct-fit replacement for 1998.5–2002 5.9L ISB (24V VP44) applications.
- Protects the bottom end by reducing torsional loads on the crankshaft and timing set.
- Quiet, smooth operation vs. worn/bulged dampers that transmit vibration.
- Built to Cummins standards for durability and long service life.
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1998.5–2002 | 5.9L ISB (24V VP44) | Ram 2500/3500 |
Industrial/Medium-Duty: Broad 6B/ISB/QSB usage (bus, vocational truck, equipment). Verify by ESN before ordering.
Compatibility Notes:
- If the existing damper shows bulged or separated rubber, replace immediately to prevent crankshaft damage.
- Use a new damper bolt on reassembly (Cummins 3903857) and torque to factory spec.
Specifications
- Type: Tuned vibration damper / harmonic balancer
- OE Part Number: 3918999
- Cross-References (ID): 3915069; Komatsu 6735-31-8120
- Quantity Required: 1 per engine (sold individually)
Often Paired With
- Damper bolt: 3903857 (single-use; replace on install)
- Front crankshaft seal kit (inspect/replace if leaking)
- Serpentine belt (replace if glazed or cracked)
What’s In The Box
- (1) Genuine Cummins Harmonic Balancer / Vibration Damper (3918999)
- Hardware and seals sold separately (see “Often Paired With”).
Installation Tips
- Mark belt routing and verify pulley alignment before removal.
- Inspect the old damper for bulging, cracks, or rubber separation.
- Always use a new damper bolt; clean threads and torque to factory spec.
- After start-up, check for runout and abnormal vibration.
FAQ
WILL THIS FIT MY 1998.5–2002 5.9L CUMMINS RAM?
Yes—3918999 is the OE harmonic balancer for late 2nd-gen 5.9L 24-valve (VP44) Ram 2500/3500. Confirm by VIN/ESN if unsure.
IS THIS THE SAME AS 3915069?
3915069 is commonly listed as an alternate/cross number for the same 98.5–02 5.9L application. Order by ESN when possible.
DO I NEED A NEW BOLT?
Yes. The damper bolt is single-use. Replace with Cummins 3903857 and torque to spec.
WHAT ARE SIGNS MY DAMPER HAS FAILED?
Bulging or extruded rubber, wobble/runout, increased vibration, belt noise, or unexplained crank sensor faults.
IS THIS A GENUINE CUMMINS PART?
Yes—OE Cummins 3918999 for proper fit and durability.
