Product Description
Interstate-McBee M-3944593 Exhaust Manifold Bolt – 89–18 5.9L/6.7L Cummins
Heavy-duty hex-flange exhaust manifold bolt engineered to OEM dimensions for 1989–2018 Cummins B-Series / ISB 5.9L & 6.7L applications. Built for reliable clamp load, heat-cycle durability, and an OEM-equivalent fit at an aftermarket price. Sold individually; 12 required per manifold.
- Direct-fit replacement: OEM-equivalent form, fit, and function.
- Heat-resistant materials: Retains clamp load through thermal cycling to help prevent leaks.
- Aftermarket value: Interstate-McBee quality at a fraction of OEM bolt pricing.
- Sold individually: Order quantity to match your repair; most manifolds use 12.
Specifications
| Manufacturer | Interstate-McBee |
|---|---|
| Part Number | M-3944593 |
| OEM Cross-Reference | Cummins 3944593 (replaces/related: 3901448) |
| Thread / Size | M10 × 1.5 × 65 mm (hex flange head) |
| Position | Exhaust manifold to cylinder head |
| Quantity Required | Typically 12 per manifold (sold individually) |
| Notes | Some applications use spacer 3945252 on select bolt locations |
Vehicle Fitment
Always verify by engine serial number (ESN) when possible.
- Dodge Ram 2500/3500 – 5.9L Cummins
- 1989–1993 12-Valve 6BT
- 1994–1998 12-Valve 6BT
- 1998.5–2002 24-Valve ISB
- 2003–2007 24-Valve ISB (common-rail)
- Dodge/Ram 2500/3500 – 6.7L Cummins
- 2007.5–2018 ISB 6.7L
- Other Cummins platforms: Widely used across B-Series / ISB and select ISC/8.3L applications; confirm by ESN.
Install Tips
- Clean threads and mating surfaces; chase threads if necessary to ensure accurate torque.
- Follow the Cummins service manual for torque and sequence; re-torque if procedure calls for it.
- Use anti-seize only if specified by service information; otherwise install dry/clean oiled per manual.
- On models requiring a spacer, use the correct 3945252 spacer at the designated bolt locations.
Warranty
Interstate-McBee new hardware carries manufacturer warranty coverage. Contact us for specific terms on fasteners.
Why Buy From CPP Diesel
- Tech-backed fitment support and ESN verification.
- Fast shipping and hassle-free returns.
- Curated Cummins hardware—match bolts, spacers, gaskets, and manifold kits in one order.
FAQ
How many bolts do I need?Most 5.9L/6.7L B-series manifolds use 12 bolts. Check your specific manifold casting to confirm.
What are the thread and length?
The common specification is M10 × 1.5 thread, 65 mm length with a hex-flange head.
Does this bolt fit both 5.9L and 6.7L?
Yes—this hardware is used across many 1989–2018 5.9L and 6.7L Cummins applications. Verify by ESN.
Do some locations require a spacer?
Yes. Certain years/engines use spacer 3945252 on specific bolt locations. Reuse the spacer if serviceable or replace as needed.
Product Videos
Custom Field
YEAR 1989-2018
MAKE DODGE
ENGINE 5.9L,6.7L
