Product Description
Keep your ISB Cummins timing rock-solid with the CUMMINS 5273412 OEM CRANKSHAFT GEAR. This genuine Cummins drive gear presses onto the crankshaft and meshes with the cam gear to maintain precise valve and injection timing on 2003–2018 Ram 5.9L and 6.7L engines. Built to OE tooth geometry and hardness, it’s the right choice when you’re rebuilding, repairing front cover damage, or fixing a jumped/worn timing set.
Features & Benefits
- Genuine Cummins 36-tooth spur crankshaft drive gear for ISB platforms (no guesswork on fit).
- OE press-fit design to prevent timing slip under load or high RPM towing conditions.
- Correct tooth profile and heat-treat for quiet, long-life operation in heavy-duty use.
- Maintains precise cam-to-crank synchronization to protect power, spool-up, and emissions.
- Ideal whenever the crank snout, front cover, or timing set has been damaged or contaminated.
Verified Fitment – Automotive
Designed primarily for common-rail Ram truck applications (verify by VIN/ESN):
- 2003–2007 Ram 2500/3500 – 5.9L ISB (24V common-rail)
- 2007.5–2018 Ram 2500/3500 – 6.7L ISB (24V common-rail)
Industrial / Off-Highway: Also used on select ISB/QSB 4.5/5.9/6.7 engines. For generators, medium-duty trucks, and equipment, always confirm by Cummins ESN before ordering.
Cross-Reference (Identification Only)
Common identification numbers that reference this gear include: Cummins 3949357, Cummins 3965389, Mopar 5086726AB, and aftermarket reference PAI 171872. Use these only as ID helpers—always match to your engine serial number for final confirmation.
Related Cummins Components at CPP Diesel
Refresh the whole front gear drive and sealing system with matching Cummins OEM parts:
- CUMMINS 5273413 OEM CAMSHAFT GEAR – ISB 5.9L/6.7L (2003–2018) – mates directly with crank gear 5273412 in the timing set.
- CUMMINS 3802820 OEM FRONT CRANKSHAFT SEAL W/ WEAR SLEEVE – 5.9L/6.7L (1989–2018) – front main seal kit with wear sleeve for grooved crank snouts.
- CUMMINS 3804899 OEM FRONT CRANKSHAFT SEAL – 5.9L/6.7L – OE front crank seal when a sleeve kit is not required.
- CUMMINS 3970305 OEM TIMING GEAR HOUSING – ISB 5.9L – replacement timing gear housing for damaged or corroded fronts.
- CUMMINS 3929027 OEM CRANKSHAFT GEAR – RAM 5.9L (1989–2002) – use this earlier B-Series gear for 1989–2002 applications instead of 5273412.
What’s In The Box
- (1) Genuine Cummins crankshaft drive gear – part number 5273412
Installation Notes
- Remove the old gear with an appropriate puller/bearing splitter; do not cut into the crank snout.
- Thoroughly clean the crankshaft nose and inspect the keyway, timing marks, and mating cam gear.
- Heat the new gear per Cummins procedure and press it on squarely, aligning timing marks correctly.
- Verify gear is fully seated against the crank shoulder and re-check cam/crank timing before reassembly.
- Anytime gear damage or debris is present, change engine oil and filter after repair.
Specifications for cummins 5273412
| Attribute | Value |
|---|---|
| Brand | Cummins Genuine OEM |
| Part Number | 5273412 |
| Component Type | Crankshaft drive / timing gear (spur) |
| Tooth Count | 36 teeth |
| Primary Applications | 2003–2018 Ram 2500/3500 with 5.9L & 6.7L ISB; select ISB/QSB 4.5/5.9/6.7 industrial (verify by ESN). |
| UPC | 193807105662 |
| GTIN | 193807105662 |
| Cross Reference (ID) | Cummins 3949357; Cummins 3965389; Mopar 5086726AB; PAI 171872 (aftermarket ID only). |
| Quantity Required | 1 per engine (sold individually) |
| Shipping Info | Approx. package size 5.30" W x 2.90" H x 6.20" D; ships from CPP Diesel, typically via ground service. |
| E-Codes / Emissions | Not an emissions-controlled component; no specific E-code listing. |
| Prop 65 | Not specifically listed by the manufacturer. Follow standard shop safety practices when handling oils, solvents, and metal components. |
FAQ
Yes—Cummins 5273412 is the OE-style crankshaft drive gear widely used on 2003–2007 5.9L ISB and 2007.5–2018 6.7L ISB Ram 2500/3500 applications. Always confirm against your VIN/ESN or Cummins QuickServe listing before ordering, especially for industrial and cab-chassis builds.
HOW DOES THIS DIFFER FROM EARLIER 5.9L CRANK GEARS LIKE 3929027?
5273412 is targeted at common-rail ISB platforms (2003+). Earlier 12V/VP44 B-Series engines typically use CUMMINS 3929027 OEM CRANKSHAFT GEAR – RAM 5.9L (1989–2002). If you’re working on a 1989–2002 truck, that earlier gear is usually the correct choice.
WHAT ARE THE COMMON CROSS-REFERENCE NUMBERS FOR 5273412?
Typical ID cross-references include Cummins 3949357 and 3965389, Mopar 5086726AB (Chrysler/Ram catalog number), and aftermarket reference PAI 171872. These are for identification only—match to your ESN to eliminate mistakes.
WHAT OTHER CUMMINS PARTS SHOULD I REPLACE WHILE I’M IN THE FRONT COVER?
Many technicians pair this gear with a fresh cam gear and seals. Popular Cummins options at CPP Diesel include:
- CUMMINS 5273413 camshaft gear to restore the full gear mesh.
- CUMMINS 3802820 front crank seal kit with wear sleeve for grooved crank snouts.
- CUMMINS 3804899 front crankshaft seal when a sleeve is not needed.
- CUMMINS 5259499 rear main crankshaft seal – 5.9L/6.7L (1989–2018) if you’re doing a full bottom-end reseal.
IS THIS A GENUINE CUMMINS PART OR AFTERMARKET?
This listing is for a genuine Cummins OEM crankshaft drive gear, part number 5273412. You get factory geometry, metallurgy, and quality control—no reboxed or “will-fit” timing gear.
