Product Description
Cummins 3929027 — Crankshaft Gear (B-Series 5.9L)
MPN: 3929027 | Also Known As: crank gear, timing gear, drive gear | Platform: B-Series 5.9L (BS3), 12V/24V
Why This Part
- ✓ OE timing accuracy—mates with cam gear to maintain precise valve timing.
- ✓ Direct-fit for 1989–2002 5.9L 12V/24V B-Series applications.
- ✓ Hardened steel construction for durability under load.
- ✓ Ideal during timing set refresh, front cover work, or engine rebuilds.
Quick Specs
| Type | Crankshaft timing gear |
|---|---|
| OE Part # | 3929027 |
| Material | Hardened steel |
| Qty Required | 1 per engine (sold individually) |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1989–2002 | 5.9L Cummins B-Series (12V & 24V) | Dodge/Ram 2500 & 3500 |
Notes: This gear is used primarily on BS3 5.9L B-Series engines. For common-rail (2003+) platforms, select the correct CR components by ESN.
Often Paired With
- Front crankshaft seal & timing cover gasket set
- Camshaft gear (match to your timing set)
- Crank damper bolt & washer (replace if stretched or corroded)
- Fresh engine oil after front cover/timing work
What’s In The Box
- (1) Genuine Cummins Crankshaft Gear (3929027)
- Related gaskets/hardware sold separately (see “Often Paired With”).
Install Tips
- Inspect keyway and mating surfaces; replace worn keys/bolts.
- Align timing marks per service manual; verify backlash as specified.
- Torque fasteners to spec; recheck after initial run-in.
FAQ
WILL THIS FIT MY 1989–2002 5.9L CUMMINS RAM?Yes—3929027 is used on 5.9L 12-valve and 24-valve B-Series engines found in 1989–2002 Ram 2500/3500 (verify by VIN/ESN).
IS THIS THE CRANKSHAFT “TIMING/DRIVE” GEAR?Correct—this is the crankshaft timing/drive gear that meshes with the camshaft gear to maintain engine timing.
IS THIS A GENUINE CUMMINS PART?Yes—OE Cummins 3929027 with factory geometry and metallurgy.
WHAT ENGINES OUTSIDE OF RAM USE THIS GEAR?It’s used primarily on BS3 5.9L B-Series applications. For industrial 4B/6B usage, confirm by ESN.
WHAT ELSE SHOULD I REPLACE DURING TIMING SERVICE?Front main seal, timing cover gasket set, and any worn fasteners or keys. Inspect the cam gear and idlers while you’re in there.
