Interstate-McBee M-3929881 Multi-Layer Exhaust Manifold Gasket – 89–98 5.9L Cummins (12-Valve)

OEM-style multi-layer steel (MLS) exhaust manifold gasket engineered for 1989–1998 Dodge Ram 2500/3500 5.9L Cummins 12-valve applications. Designed to handle high EGTs and thermal cycling while maintaining a reliable seal between the cylinder head and exhaust manifold. Order quantity: six (6) gaskets per engine.

• MLS construction: Laminated steel layers resist blowouts and warping under heat.
• Direct-fit replacement: Matches OEM footprint for easy alignment and install.
• Performance-ready: Ideal for stock or tuned 12-valve engines with elevated EGTs.
• Aftermarket value: Interstate-McBee quality at a lower cost than OEM boxed parts.

Specifications

Vehicle Fitment

Verify by engine serial number (ESN) for best results.

• Dodge Ram 2500/3500 — 5.9L Cummins 12-Valve (6BT)
  • Model Years: 1989–1998
• Also used on select Cummins B-Series (4BT/6BT) industrial variants.

Installation Notes

• Remove old gasket material completely; clean mating surfaces until smooth and oil-free.
• Follow Cummins service manual torque sequence/specs; retorque if the manual calls for it after heat-cycle.
• Consider new manifold bolts/hardware during service to maintain clamping force.

Warranty

Interstate-McBee new engine parts for diesel applications are generally covered for up to 24 months from installation (no mileage/hour limit). See manufacturer policy for exact terms.

Why Buy From CPP Diesel

• Fitment-first support with ESN verification on B-Series Cummins.
• Fast shipping, easy returns, and real diesel techs on the phones.
• Curated components that pair perfectly with common 12-valve upgrades.

FAQ