Product Description
MBRP DS9405 is a 4" T409 stainless down pipe from the Armor Plus series engineered for 2003–2004 Dodge Ram 2500/3500 trucks with the 5.9L Cummins. Built from 16-gauge T409 and backed by a lifetime warranty, it’s a direct-fit, bolt-on upgrade designed to improve flow and help reduce EGTs on 305 HP models.
- Material: T409 Stainless (Armor Plus Series)
- Tubing Size: 4"
- Warranty: Lifetime (manufacturer)
- UPC: 882963100542
- SKU: MBRDS9405
Fitment
- 2003–2004 Dodge Ram 2500 / Ram 3500 – 5.9L Cummins (305 HP models)
- Excludes 2004.5 models and trucks equipped with a catalytic converter.
Cross-Reference / Alternatives (MBRP-only)
- Aluminized alternative: MBRP DAL405 4" Down Pipe (Aluminized)
- Complete turbo-back (4"): MBRP S6104AL 4" Turbo-Back (Aluminized)
- Complete turbo-back (5"): MBRP S61140AL 5" Turbo-Back (Aluminized)
Helpful Notes
- T409 stainless offers strong value and lifetime coverage; surface discoloration is normal with heat. For harsh winter climates, regular cleaning helps minimize cosmetic corrosion.
- Direct-fit to OEM hangers; typical install time ~1.5–2 hours with hand tools.
FAQ
Will DS9405 fit my 2004.5 truck?
No. DS9405 fits 2003–early 2004 (305 HP) models only. It does not fit 2004.5+ (emissions/other changes).
What’s the difference between T409 and aluminized?
T409 stainless resists rust better than aluminized and carries a lifetime warranty. Aluminized (DAL405) is a budget-friendly alternative.
Does this include all clamps and hardware?
The DS9405 is the down pipe component. Reuse existing hardware or add needed clamps during install as required by your system configuration.
