HE400VG Turbo and Manifold Kit for ISX15 and X15: Why Diesel Mechanics Are Replacing Both at Once

If you work on ISX15 and X15 engines long enough, you start to notice a pattern: turbo problems and manifold problems rarely arrive alone. A cracked manifold raises EGTs and starves the turbo of drive pressure. A failing VGT creates backpressure spikes that accelerate manifold cracking. By the time the truck limps into the shop, both components are compromised — even if only one is throwing codes.

That's the reason Diesel Power Source® built the HE400VG Turbo and Manifold Kit as a complete package. One box. One installation. Both failure points addressed at the same time.

What's in the Kit

The DPS HE400VG Turbo and Manifold Kit includes everything required for a complete installation on 2016–2024 Cummins ISX15 and X15 engines:

• HE400VG VGT turbocharger with 7-blade forged machined compressor wheel (67mm or 70mm options) and an 11-blade turbine wheel (72mm inducer, 68mm exducer)
• Brand-new electronic VGT actuator — pre-calibrated from the factory, not remanufactured
• DPS high-flow 3-piece press-fit exhaust manifold — available in EGR and Non-EGR configurations
• Complete hardware kit including bolts, spacers, gaskets, turbo studs, and nuts
• No core charge

Everything arrives ready to install. No separate sourcing of hardware, no actuator calibration required after installation.

The 70mm Compressor Wheel — Why It Matters

The factory ISX15 HE400VG comes with a 64mm or 67mm compressor wheel depending on the application. Diesel Power Source® offers an exclusive 70mm compressor wheel option that is not available from any other source.

The difference in real-world terms:

• 67mm compressor — supports approximately 575 HP, direct replacement for most factory applications
• 70mm compressor (DPS exclusive) — supports approximately 700 HP, better top-end airflow, measurably lower EGTs under sustained load

Both options retain the factory VGT system, which means exhaust brake function stays intact and the ECU continues to control boost through the variable geometry vanes — no tuning required for either wheel size.

Why the Manifold Matters as Much as the Turbo

The DPS ISX15 exhaust manifold is a press-fit, 3-piece design built from High Silicon Molybdenum Ductile Iron (HSMD). That material and construction choice is deliberate.

The factory ISX15 manifold is a single-piece casting. On a six-cylinder engine this long, thermal cycling creates enormous stress. Over time, single-piece manifolds crack along the center divider or at the turbo mounting flange — sometimes both. By 400,000–500,000 miles, manifold cracking is nearly universal on high-mileage ISX engines.

The DPS 3-piece design uses hydraulically pressed expansion joints that allow each section to expand and contract independently under heat cycles rather than transferring that stress to the casting. The result is a manifold that flows approximately 22% more than the factory unit and is built to outlast it significantly.

Every manifold leaves the facility pressure-tested and verified flat. CFD-tested runner geometry reduces turbulence and lowers exhaust drive pressure — which means the turbo spools faster and EGTs run approximately 75–100°F cooler under load.

EGR and Non-EGR Configurations

The kit is available in both configurations:

EGR version — includes the port for the bellows-style connector that routes exhaust to the EGR cooler. Correct for trucks with the factory emissions system intact.

Non-EGR version — eliminates the EGR port, routing all exhaust directly to the turbo. Designed for trucks running without the factory EGR system. The Non-EGR manifold also includes a pre-tapped back pressure sensor port — the only ISX15 non-EGR manifold on the market with this feature — which maintains ECU communication without requiring additional fabrication.

Both versions use identical HSMD construction and deliver the same 22% flow improvement.

Compatible Platforms

The HE400VG Turbo and Manifold Kit fits 2016–2024 Cummins ISX15 and X15 engines on CM2250 and CM2350 platforms, including Freightliner, Peterbilt, Kenworth, Volvo, International, and Western Star.

ESN (Engine Serial Number) verification is required before shipment. ISX15 and X15 engines have numerous chassis-specific variants that affect fitment. Diesel Power Source® verifies every ESN before the kit ships to ensure correct configuration.

This kit is not compatible with HE451VE applications.

One Job, One Labor Cost

The practical argument for replacing both components at once is straightforward. If a manifold is cracked and a turbo is failing on the same engine, doing the work separately means pulling the same components twice, paying labor twice, and taking the truck out of service twice.

The DPS HE400VG Turbo and Manifold Kit is priced to make the combined installation cost less than sourcing and installing each component separately — and the performance gain from having both components matched and optimized from day one is measurably better than replacing one while leaving a compromised component behind.

Specifications

Spec	Detail
Fitment	2016–2024 Cummins ISX15 / X15
Platforms	CM2250, CM2350
Compressor options	67mm (approx. 575 HP) or 70mm (approx. 700 HP)
Turbine wheel	72mm inducer / 68mm exducer, 11-blade
Actuator	Brand-new electronic VGT, pre-calibrated
Manifold design	3-piece press-fit HSMD ductile iron
Manifold configs	EGR and Non-EGR
Flow improvement	Approx. 22% over factory
EGT reduction	Approx. 75–100°F under load
Core charge	None
ESN required	Yes

Shop the HE400VG Turbo and Manifold Kit →

Questions about fitment or configuration? Call 801-930-8404 or email sales@dieselpowersource.com.