Product Description
DIAMOND EYE K4209S is a 4.0" 409 stainless steel turbo-back, single, side-exit exhaust system for 1989–1993 Dodge Ram 2500/3500, 2x4 (2WD) only. Built for first-gen 5.9L Cummins trucks, it delivers lower EGTs, improved flow, and a clean, classic sound with durable T409 tubing and mandrel bends.
Fitment and material verified from the Diamond Eye catalog (K4209S page) and official install sheet.
Fitment Details
- Years/Platform: 1989, 1990, 1991, 1992, 1993 Dodge Ram 2500/3500, 2WD (2x4) only.
- Engine: 5.9L Cummins (VE-pump first-gen).
- Configuration: Turbo-back, single, side exit, 4.0" diameter.
- Material: 409 stainless steel.
FAQ: WILL THIS FIT 4WD?
No. K4209S is for 2WD applications. For a stainless 4WD alternative, see the MBRP system linked below in Cross-Reference (4WD only).
FAQ: DOES IT INCLUDE A DOWNPIPE?
Yes—this is a full turbo-back kit that routes from the turbo outlet to the tail section for the specified application.
FAQ: IS IT CARB APPROVED?
No. Most turbo-back systems for these model years are not CARB legal for on-road use in California. Check local regulations before purchase.
Cross-Reference / Alternatives (MBRP-only, links point to working CPP Diesel pages)
- MBRP S6148AL – 4" Turbo-Back, 2WD, aluminized steel (budget alternative): View on CPP Diesel
- MBRP S6150409 – 4" Turbo-Back, 4WD only, T409 stainless (different drivetrain): View on CPP Diesel
Specifications
| Brand | Diamond Eye Performance |
|---|---|
| MPN | K4209S |
| UPC | 841963103137 |
| GTIN | 841963103137 (GTIN-12 / UPC-A) |
| Material | 409 Stainless Steel |
| System Type | 4" Turbo-Back, Single, Side Exit |
| Vehicle Fitment | 1989–1993 Dodge Ram 2500/3500, 2WD (2x4), 5.9L Cummins |
| Shipping | Ships ground in oversized carton; signature may be required |
| Prop 65 | WARNING: Cancer and Reproductive Harm — www.P65Warnings.ca.gov |
