12V Cummins T4 Exhaust Manifold Hardware & Gasket Upgrade Kit | 1989–1998 5.9L
The Diesel Power Source® 12V Cummins T4 Manifold Hardware & Gasket Upgrade Kit is a complete add-on package designed to fully install the DPS T4 12-Valve Exhaust Manifold on 1989–1998 5.9L Cummins engines. It includes every gasket and fastener needed for both the manifold-to-head install and the T4 turbo flange install — sourced together so you don't have to chase parts mid-build.
This kit replaces the standard flange bolts found in the manifold's base hardware kit with a full stud-and-nut configuration, the preferred mounting method for high-EGT and high-boost applications. Multi-Layer Steel (MLS) gaskets resist burnout, blow-through, and warping far better than single-layer alternatives, and the divided T4 turbo flange gasket and oil drain gasket are included to complete the install.
Designed as the recommended upgrade to the DPS T4 12V Exhaust Manifold (MAN0199). The base kit included with the manifold ships with standard flange bolts and the line relocation bracket. This upgrade adds the gaskets, stud-and-nut hardware, and turbo install components needed to complete a full T4 manifold and large-frame turbo install in one purchase.
Built for High-Horsepower 12V Builds
The DPS T4 12V manifold is designed for owners running larger frame turbochargers — S300, S400, and compound turbo setups that need more flow than a T3 manifold can deliver. This hardware kit was built specifically to support that level of build, with stud-style manifold mounting that handles the higher exhaust energy and heat loads these setups produce.
Stud-and-Nut Manifold Mounting
Studs provide more consistent clamping load than bolts and resist fastener fatigue from repeated thermal cycling — critical for an exhaust manifold that sees hundreds of heat cycles a year on a high-output 12V build. Studs also make future manifold removal far easier; you back off nuts instead of breaking loose corroded bolt threads in the head.
Multi-Layer Steel Gaskets
MLS gaskets use stacked stainless layers to seal the variable surfaces between the manifold and head. They handle higher boost, higher EGTs, and more aggressive tuning than single-layer gaskets without burning through or warping — exactly what a T4-sized turbo build demands.
T4 Divided Flange Gasket Included
The DPS T4 12V manifold uses a divided pulse design, and this kit includes the matching T4 divided flange gasket along with the turbo oil drain gasket. No separate sourcing required.
Who This Kit Is For
- Owners of 1989–1998 Dodge Ram 2500 and 3500 trucks running the 5.9L 12-Valve Cummins (B5.9 12V)
- First-gen and second-gen Cummins builders installing the DPS T4 12V Exhaust Manifold (MAN0199)
- Builds running S300, S400, or other large-frame T4 turbochargers
- Compound turbo setups and high-horsepower single turbo applications
- Sled pull, race, and competition 12V builds
- Builders who want all install hardware and gaskets in a single purchase
What's Included
| Qty | Component | Purpose |
|---|---|---|
| 6 | Multi-Layer Steel Manifold-to-Head Gaskets | Seals manifold to cylinder head |
| 1 | T4 Divided Turbo Flange Gasket | Seals turbo to T4 manifold flange |
| 1 | Turbo Oil Drain Gasket | Seals oil drain line to turbo |
| 12 | M10-1.5 × 20-12-16 Manifold Studs | Replaces base-kit flange bolts |
| 12 | M10-1.5 Manifold Flange Nuts | Pairs with manifold studs |
| 4 | M10-1.5 × 20-12-16 Turbo Studs | Mounts T4 turbo to manifold |
| 4 | M10-1.5 Turbo Flange Nuts | Pairs with turbo studs |
Key Features
- Full stud-and-nut manifold mounting — replaces the base kit's standard flange bolts
- Multi-Layer Steel manifold gaskets — built for high boost and high EGTs
- T4 divided turbo flange gasket included — matches the DPS T4 12V manifold's pulse-divided design
- Complete T4 turbo mounting hardware — 4 studs, 4 nuts, oil drain gasket
- Direct fit for the DPS T4 12V Exhaust Manifold (MAN0199) — no machining or modifications
- Single-source convenience — every gasket and fastener for the install in one SKU
Benefits
- Reduces manifold-bolt loosening and fastener fatigue from repeated heat cycling
- Improves long-term sealing under boost, towing, and aggressive tuning
- Makes future manifold removal easier — back off nuts instead of fighting seized bolts
- Eliminates the need to source MLS gaskets and stud kits from multiple suppliers
- Built to handle the loads of large-frame T4 turbo builds
Fitment
- 1989–1998 Dodge Ram 2500 / 3500 — 5.9L 12-Valve Cummins (B5.9 12V)
- Pairs with the Diesel Power Source® T4 12V Exhaust Manifold (MAN0199)
- Compatible with T4-flange turbochargers — S300, S400, and compound turbo setups
- Off-road, marine, agricultural, and industrial 12V B5.9 applications running T4 turbos
Note: This kit fits the DPS T4 12V Exhaust Manifold only. If you have a T3 12V manifold, see our T3 hardware and gasket kit instead. The line relocation bracket ships with the manifold base kit and is not included here.
Pairs With This Kit
Frequently Asked Questions
Not strictly. The base hardware kit included with the manifold has the bolts and line relocation bracket needed to mount the manifold to the head. This upgrade kit is for builders who also want MLS gaskets, a stud-and-nut manifold mount, and the hardware and gaskets to install their T4 turbo at the same time.
The DPS T4 12V manifold uses a pulse-divided flange design, which improves spool and turbine efficiency on large-frame turbos. A non-divided T4 gasket isn't included because it isn't needed for this manifold's flange.
Yes — as long as the turbo uses a T4 inlet flange. The T4 flange pattern on S300 (T4 configuration), S400, and most large-frame turbos is the same, and the 4 turbo studs and nuts in this kit fit the standard T4 4-bolt pattern.
Yes. The 12 manifold studs and nuts directly replace the flange bolts and stud included in the base kit. No machining, drilling, or modifications are required.
