High Flow T6 Exhaust Manifold for Cummins ISX (2002-2015) CM870 CM871 CM2250 CM2350

Heavy-Duty T6 Exhaust Manifold for 2002-2015 Cummins ISX (Class 8 HD)

What it Does: The DD-T6 exhaust manifold converts the factory turbine mounting layout on the 2002-2015 Cummins ISX to an open-breathing dual-volute T6 flange, improving exhaust gas pulse scavenging and enabling non-wastegated performance turbo conversions.

The Stock Cummins ISX Exhaust Manifold Failure Points

The OEM cast ductile-iron exhaust manifolds on the Cummins ISX (spanning CM870, CM871, CM2250, and CM2350 systems) routinely fail due to persistent thermal cycling and elevated exhaust gas temperatures (EGTs). Factory assemblies develop severe center-divider warpage, runner cracking, and sleeve erosion at the joints. These structural failures produce exhaust leaks that compromise drive pressure, contaminate engine bays with soot, and delay turbo response. Additionally, the proprietary factory turbo flange locks owners into the restrictive, high-maintenance HE500-series variable geometry turbos.

The Engineering Solution

Cast from thick-walled CF8 (304 Stainless Steel), this manifold withstands sustained high-load exhaust temperatures without sagging, scaling, or developing fatigue cracks. Designed with engineered expansion slip joints, the structure expands and contracts dynamically under heavy-haul thermal cycling, relieving lateral stress from the cylinder head studs. The pulse-tuned internal runners channel exhaust gas evenly into a divided T6 flange, reducing exhaust backpressure, dropping baseline EGTs, and maximizing drive pressure efficiency for aftermarket BorgWarner S410SX and S400-frame conversions.

Technical Specifications

Compatibility

• 2002-2007 Cummins ISX with CM870 engine control system
• 2008-2010 Cummins ISX with CM871 engine control system
• 2010-2012 Cummins ISX15 with CM2250 engine control system
• 2013-2015 Cummins ISX15 with CM2350 engine control system

Frequently Asked Questions

Does this fit the Class 8 HD ISX?

Yes, this is a direct fit for the 2002-2015 Cummins ISX equipped with the ISX15 engine platform.

Can I reuse my factory HE500-series turbocharger?

No, this manifold features a divided T6 flange engineered exclusively for aftermarket T6 turbochargers like the BorgWarner S410SX and requires aftermarket engine tuning.

The Cummins Heavy-Haul Standard

Engineered for severe duty cycles and maximum continuous gross vehicle weight ratings, this stainless steel exhaust manifold delivers the thermal durability and structural reliability necessary to keep long-haul commercial freight moving without boost-pressure drop or cracked manifold downtime.