Product description
T4 Center Mount Exhaust Manifold for Cummins 1998.5–2018 | For Aftermarket Turbos | **NOT OEM
Important: This is NOT an OEM manifold. This T4 center mount manifold is designed exclusively for aftermarket T4-flange turbochargers (S300, S400, and similar). It will NOT fit factory Holset turbochargers (HX35, HY35, HE341, HE351CW, HE351VE, HE300VG), which use T3 or T4i flanges.
The Diesel Power Source® T4 center mount exhaust manifold is a 3-piece performance manifold with a center-dump T4 turbo flange for 1998.5–2018 Dodge Ram trucks with the 5.9L 24-valve or 6.7L Cummins engine. This manifold mounts aftermarket T4-flange turbochargers in the center (2nd gen) turbo position and is designed for owners upgrading to larger S300, S400, or other T4-flange turbos for high-horsepower single turbo builds, compound turbo setups, sled pulling, or performance towing applications.
Cast from ductile iron with CFD-tested runner geometry, this manifold flows significantly more exhaust than the factory manifold while maintaining the exhaust gas velocity needed for fast turbo spool-up. The 3-piece expansion joint design eliminates the cracking and warping that destroys factory and single-piece aftermarket manifolds, including stainless steel competitors.
Who Needs a T4 Manifold?
A T4 manifold is required when upgrading from the factory turbocharger to an aftermarket turbo with a T4 inlet flange. The factory 5.9 and 6.7 Cummins manifolds use T3 or T4i flanges, which are not compatible with larger T4-flange turbos. If you are running or planning to install any of the following, you need this manifold:
- S300 turbos with T4 exhaust housing — S362, S363, S366, S369 in T4 configuration
- S400 turbos — S467, S472, S475, S478, S480, S483
- Compound turbo setups where the high-pressure turbo uses a T4 flange
- 2nd gen swap configurations on 2003–2018 trucks using a center-mount turbo position
- High-horsepower single turbo builds exceeding the airflow capacity of T3-flange turbos
- Sled pulling and drag racing builds using large-frame turbochargers
If you are keeping your factory turbo or using a T3-flange aftermarket turbo, you do not need this manifold. Use the appropriate T3 manifold for your generation instead.
Why the DPS T4 Over Steed Speed or Other Competitors
The DPS T4 center mount manifold is cast from ductile iron with a 3-piece expansion joint design. This is a critical advantage over competitor manifolds, including the Steed Speed T4:
- Stainless steel manifolds (including Steed Speed) expand and contract up to 2x more than ductile iron during thermal cycling. This extra movement stresses the cylinder head, head bolts, and gaskets, causing leaks and failures in those components over time.
- Single-piece manifolds cannot flex with temperature changes. They either crack (cast iron) or transfer all expansion force into the head (stainless).
- The DPS 3-piece design absorbs thermal expansion through the expansion joints, protecting both the manifold and the cylinder head. It stays tight, aligned, and sealed through thousands of heat cycles.
DPS designs all manifolds using CFD (Computational Fluid Dynamics) testing to optimize runner sizing and flow balance. Oversized runners from some competitors actually slow exhaust gas velocity, causing the exhaust to bottleneck at the turbo flange. DPS has tested competitor manifolds that decreased horsepower by 40 HP on a 400 HP truck due to oversized runner designs.
Key Benefits of the T4 Upgrade
- Increased Airflow — The T4 flange and optimized runners support higher exhaust volume for large-frame turbochargers that T3-flange manifolds cannot feed
- Lower Drive Pressure and EGTs — Reduced restriction through the manifold lowers exhaust backpressure and exhaust gas temperatures, especially under sustained load
- Turbocharger Flexibility — Enables the use of S300 (T4 config), S400, and other large-frame turbos not compatible with smaller factory flanges
- Faster Turbo Spool — CFD-tested pulse-divided design delivers exhaust energy efficiently to the turbine for improved throttle response
- Crack-Resistant 3-Piece Design — Expansion joints handle thermal cycling without the cracking that destroys factory and single-piece manifolds
- Center Mount Position — Turbo mounts in the center (2nd gen) location for optimal exhaust routing and clearance
