Product Description
CUMMINS 3990732 OEM TAPPET / PUSHROD COVER – 5.9L 12V (1989–1998)
Keep your 5.9L 12-valve Cummins dry and correct with this genuine Cummins 3990732 tappet / pushrod side cover. This stamped-steel cover is the OE piece that shields the pushrods and lifter valley, restoring a clean seal and factory appearance when the original has rusted, warped, or started to seep oil on your 1989–1998 Ram 2500/3500.
Why Choose Genuine Cummins 3990732
- OE-correct stamped steel cover built to Cummins specifications for long-term sealing and durability.
- Direct-fit replacement for the factory side cover on 1989–1998 5.9L 12V Ram 2500/3500 (6BT).
- Helps eliminate messy oil streaks down the block when paired with a fresh gasket and bolt grommets.
- Maintains proper crankcase ventilation and protects the pushrods from debris and underhood contamination.
- Backed by Cummins quality for consistent fit, finish, and service life.
Fitment Details
Automotive Applications:
- 1989–1993 Dodge Ram 2500/3500 – 5.9L 12V Cummins (6BT)
- 1994–1998 Dodge Ram 2500/3500 – 5.9L 12V Cummins (6BT)
Engine Platform:
- Cummins B-Series 5.9L 12-valve (6BT), Tier-1 style pushrod cover.
Important Notes:
- Not for 24-valve (1998.5–2002) ISB or later 5.9L / 6.7L common-rail engines.
- Always install with a new tappet / pushrod cover gasket and bolt grommet seals.
- Verify by engine serial number (ESN) for industrial / off-highway B-Series applications.
Cross-Reference & Related Cummins Parts
This Cummins 3990732 cover supersedes several earlier OE part numbers and pairs with other Cummins genuine components available at CPP Diesel.
- Superseded / Cross-Reference Part Numbers: 3927916, 3911821, 3910819, CUM3990732.
- Tappet / Pushrod Cover Gasket: CUMMINS 3284623 OEM TAPPET / PUSH ROD COVER GASKET – 5.9L (1989–2002)
- Tappet Cover Bolt Grommet Seals (6 required): CUMMINS 3900267 OEM TAPPET COVER BOLT GROMMET SEAL – 5.9L (1989–1998)
- Tappet Cover Noise Panel / Shield (’94–’98): CUMMINS 3924606 OEM TAPPET COVER NOISE PANEL – 5.9L 12V (1994–1998)
- Matching OEM Valve Tappets (Lifters): CUMMINS 3931623 OEM VALVE TAPPET (LIFTER) – 6BT/4BT 5.9L/3.9L (1989–1998)
Installation Tips
- Thoroughly degrease the block sealing surface and remove all old gasket material.
- Install a new Cummins 3284623 gasket and six new 3900267 grommet seals with this cover.
- Snug hardware in an even pattern along the cover and torque to the factory spec.
- After the first heat cycle, re-check fasteners and inspect for any oil seepage.
Specifications for cummins 3990732
| Brand | Cummins (Genuine OEM) |
| Cummins Part Number | 3990732 |
| Superseded / Alt Numbers | 3927916, 3911821, 3910819, CUM3990732, PAI 141342 (cross ref only) |
| Component Type | Tappet / Pushrod Side Cover (Engine Side Cover) |
| Engine Family | Cummins B-Series 5.9L 12V (6BT) |
| Primary Vehicle Fitment | 1989–1998 Dodge Ram 2500/3500 5.9L 12-valve Cummins |
| Material | Stamped steel |
| Quantity Required | 1 per engine |
| Shipping Weight | Approx. 6.9 lb (3.1 kg) |
| Approx. Package Dimensions | 10.88" W × 9.00" H × 30.88" L (shipping carton) |
| UPC | Not specified by manufacturer |
| GTIN | Not specified by manufacturer |
| Cross Reference (Function Only) | Earlier Cummins pushrod covers 3927916, 3911821, 3910819; may also interchange with PAI 141342 in some applications (confirm by ESN). |
| E-Codes / Emissions | Non-emissions engine component (no specific E-code listing). |
| Prop 65 Warning | This product can expose you to chemicals including engine oil and diesel exhaust, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov. |
| Country of Origin | USA (typical for OEM Cummins 3990732; exact origin may vary by batch) |
FAQ
WILL THIS COVER FIT MY 1989–1998 5.9L 12-VALVE CUMMINS RAM?
Yes. Cummins 3990732 is the correct OEM tappet / pushrod side cover for most 1989–1998 5.9L 12V Ram 2500/3500 applications. If you are unsure, confirm by VIN or engine serial number before ordering.
DOES THIS KIT INCLUDE THE GASKET AND BOLT GROMMETS?
No. This listing is for the metal cover only. Pair it with a new CUMMINS 3284623 gasket and six CUMMINS 3900267 bolt grommet seals to prevent leaks.
WILL THIS WORK ON 24-VALVE OR COMMON-RAIL 5.9L / 6.7L ENGINES?
No. 24-valve and later common-rail engines use different cover and gasket designs. This 3990732 cover is for 12-valve B-Series applications only.
WHEN SHOULD I REPLACE THE TAPPET / PUSHROD COVER?
If you see oil streaks down the side of the block, heavy rust or pitting on the cover, or repeated gasket failures even with new gaskets and grommets, the original cover is likely warped or damaged and should be replaced.
IS CUMMINS 3990732 A GENUINE OEM PART OR AFTERMARKET?
This is a genuine Cummins OEM tappet / pushrod cover sourced through CPP Diesel, not an aftermarket reproduction.
