Cummins ISX15 / X15 Non-EGR Exhaust Manifold for Stock Turbo (2010–2024)
The Diesel Power Source® Non-EGR Exhaust Manifold is a high-flow replacement manifold for 2010–2024 Cummins ISX15 and X15 engines running non-EGR configurations. This manifold eliminates the factory EGR feed port and routes all exhaust gas directly to the turbocharger, improving exhaust flow by up to 22% over the stock manifold and reducing exhaust gas temperatures by approximately 75–100°F.
Built as a press-fit 3-piece design, this manifold uses hydraulically pressed joints instead of the seal-type connections found on factory manifolds. This construction eliminates the exhaust leaks that commonly develop at the joint seals on OEM ISX manifolds, reducing the risk of roadside breakdowns and repeat repairs.
The DPS Non-EGR manifold is cast from High Silicon with Molybdenum Ductile Iron (HSMD), the same premium material grade used in the most demanding commercial diesel applications. This material resists warping, cracking, and center divider erosion from the extreme heat cycling that Class 7 and Class 8 trucks produce during sustained load.
Ceramic Coating Options (1000° vs 2400°)
Both coating options provide corrosion protection and thermal management. Choose the option that best matches your operating conditions.
| Coating | Temperature Rating | Recommended For |
|---|---|---|
| Standard Ceramic | Up to 1000°F | Most applications, daily operation, standard duty cycles |
| Premium Ceramic | Up to 2400°F | Higher duty cycles, extended idle, elevated EGT applications, heavy towing |
Fitment
This manifold fits Cummins ISX15 and X15 engines from 2010–2024 in non-EGR configurations. It is designed for use with the factory HE400VG (or HE451VE) stock turbocharger and bolts directly to the stock turbo mounting flange.
Compatible engine platforms include CM871, CM2250, and CM2350 (and select X15 variants). Please provide your Cummins Engine Serial Number (ESN) when ordering so our team can verify compatibility before shipment.
Important: This is the Non-EGR version of the DPS ISX15 exhaust manifold. It does not include an EGR feed port and is intended for trucks that are not using the factory EGR system. If your truck requires the EGR bellows connection, see the DPS Cummins ISX15 / X15 EGR Exhaust Manifold instead.
EGR vs Non-EGR Exhaust Manifolds Explained
All 2010–2024 Cummins ISX15 and X15 engines were factory-equipped with EGR (Exhaust Gas Recirculation) systems. The factory EGR exhaust manifold includes a port that routes a portion of exhaust gas to the EGR cooler and valve to reduce NOx emissions.
The DPS Non-EGR manifold eliminates this port and provides a direct, uninterrupted exhaust flow path to the turbocharger. This design is used on trucks operating in non-EGR configurations, including off-highway applications, export markets, and other non-emissions setups. Removing the EGR feed port simplifies the exhaust path and contributes to the improved airflow and lower EGTs this manifold delivers.
| Manifold Type | Description | OE Cross Reference |
|---|---|---|
| EGR Exhaust Manifold | Includes EGR feed port for emissions system routing (bellows connection) | 3687063, 3692604, 3689251, 3687062 |
| Non-EGR Exhaust Manifold | No EGR port. Direct exhaust flow to turbocharger | Aftermarket performance design (replaces OE assemblies listed above when EGR is removed) |
OEM Exhaust Manifold Cross Reference — Cummins ISX15 / X15
This DPS Non-EGR manifold replaces the factory Cummins EGR exhaust manifold assemblies on trucks where the EGR system has been removed. Common OEM part numbers associated with the factory ISX15 / X15 manifold include:
Complete Assembly Numbers (Superseded)
- Cummins 3687063
- Cummins 3692604
- Cummins 3689251
- Cummins 3687062
Center Section (Turbo Mount) Casting Numbers
- 3687063
- 3689251
- 3687062
- 3685284
- 3683789
End Section Casting Numbers
- 3683870
- 3685999
- 3685099
- 3684295
Truck technicians often identify manifolds by the casting number stamped on the part. If your existing manifold carries any of the numbers listed above, this DPS replacement is compatible with your engine platform.
Why the ISX / X15 Manifold Uses a 3-Piece Design
The Cummins ISX15 exhaust manifold uses a 3-piece construction consisting of a front section, center section (turbo mount), and rear section. This design allows each section to expand independently under extreme exhaust temperatures, which significantly reduces the cracking and warping failures common on single-piece manifold designs. The DPS version improves on this concept by hydraulically pressing the sections together, eliminating the seal-type joints that tend to leak on factory manifolds over time.
Common ISX15 / X15 Exhaust Manifold Failure Symptoms
- Visible exhaust leaks at manifold joints or head gasket surfaces
- Cracking along the center divider or turbo mounting flange
- Elevated exhaust gas temperatures (EGTs) under load
- Sluggish turbo spool or reduced boost pressure
- Soot buildup around manifold bolt heads or gasket surfaces
- Exhaust odor in the cab during operation
- Warped manifold flanges causing repeated gasket failures
If your ISX15 or X15 is showing any of these symptoms, the exhaust manifold may be cracked, warped, or leaking at the joints. The DPS press-fit design and HSMD material address each of these common failure points.
Bundle Option
Replacing the turbo and manifold together reduces labor time and ensures proper alignment between components. See the complete turbo and manifold package here: HE400VG Turbo & Exhaust Manifold Kit for Cummins ISX15 / X15
What's Included
- (1) DPS 3-Piece Press-Fit Exhaust Manifold for Cummins ISX15 / X15 (Non-EGR)
- Ceramic coated finish (1000° or 2400° based on selection)
- Pre-tapped OEM sensor port
- Pre-tapped pyro and pressure ports
Not Included (Sold Separately)
- Manifold Hardware Kit — Bolts, spacers, turbo studs, and nuts
- Manifold Gasket & Turbo Flange Kit
- Turbo supply and drain lines
Note: When upgrading to any gasket kit option, the upgraded components replace the standard bolts and gaskets. Standard hardware will not be included with the upgrade selection.
Why Choose Diesel Power Source?
Diesel Power Source® engineers Cummins exhaust manifolds for the demands of real-world commercial trucking. This ISX15 Non-EGR manifold is designed for long service life under sustained load and extreme heat cycling.
- 22% Exhaust Flow Increase — CFD tested for improved flow over stock manifolds
- 75–100°F EGT Reduction — Lower exhaust temperatures reduce stress on the turbo, head gaskets, and valves
- Press-Fit 3-Piece Construction — Hydraulically pressed joints eliminate the exhaust leaks common on seal-type OEM manifolds
- HSMD Ductile Iron — High Silicon with Molybdenum Ductile Iron resists cracking, warping, and center divider erosion
- Pre-Tapped Sensor Ports — OEM sensor port, pyro port, and pressure port ready for installation
- Fits Stock Turbo — Bolts directly to the factory HE400VG or HE451VE turbocharger
- ESN-Verified Fitment — Our team confirms compatibility before shipment
Warranty
This Diesel Power Source® exhaust manifold includes a 1-year limited warranty and is backed by our technical support team for fitment and installation assistance.
Related ISX15 / X15 Exhaust Manifold Resources
- Cummins ISX15 / X15 EGR Exhaust Manifold (With Bellows Connection)
- HE400VG Turbo & Exhaust Manifold Kit for ISX15 / X15
- ISX15 / X15 Exhaust Manifold Hardware Kit
- ISX15 / X15 Manifold Gasket & Turbo Flange Kit
- ISX15 / X15 Exhaust Manifold Bolt & Spacer Kit
- HE400VG Turbo Replacement for Cummins ISX15 / X15
- EGR vs Non-EGR Exhaust Manifold | Cummins ISX15 X15 Guide
Frequently Asked Questions
The Cummins ISX15 / X15 exhaust manifold uses a 3-piece design (front section, center turbo mount section, and rear section) to allow each piece to expand independently under extreme exhaust temperatures. This significantly reduces cracking and warping compared to single-piece designs. The DPS version improves on this by hydraulically pressing the sections together, eliminating the seal-type joints that commonly leak on factory manifolds.
The 1000° ceramic coating is the standard option suitable for most operating conditions and daily commercial use. The 2400° premium ceramic coating provides a higher-temperature thermal barrier and is recommended for trucks that experience extended idle, elevated EGTs, heavy towing, or higher-than-normal duty cycles.
Yes. This Non-EGR exhaust manifold bolts directly to the factory HE400VG and HE451VE turbochargers used on Cummins ISX15 and X15 engines. The turbo mounting flange matches the stock configuration. Please provide your Engine Serial Number (ESN) so our team can verify compatibility before shipment.
The EGR exhaust manifold includes a port that routes exhaust gas to the factory EGR cooler and valve for emissions compliance. The Non-EGR manifold eliminates this port and sends all exhaust directly to the turbocharger, providing a simpler and more efficient exhaust flow path. If your truck still uses the factory EGR bellows connection, you need the EGR version
Yes. This Non-EGR exhaust manifold bolts directly to the factory HE400VG and HE451VE turbochargers used on Cummins ISX15 and X15 engines. The turbo mounting flange matches the stock configuration. Please provide your Engine Serial Number (ESN) so our team can verify compatibility before shipment.
