DIAMOND EYE K4209S-HX40 TURBO BACK EXHAUST 89-93 DODGE RAM 2500/3500 5.9L CUMMINS 2X4 4 INCH STAINLESS TURBO BACK SINGLE HX40

DIAMOND EYE K4209S-HX40 is a 4.0" 409 stainless turbo-back single exhaust engineered for 1989–1993 Dodge Ram 2500/3500 5.9L Cummins 2WD (2x4) trucks. This version includes an HX40-flange downpipe for builds running an aftermarket turbo with an HX40 outlet profile. Mandrel-bent tubing maximizes flow and reduces EGTs while reusing OE-style hangers for a clean, bolt-on install.

Note: This HX40 kit is intended for aftermarket HX40-outlet turbos and will not fit a stock first-gen turbo. Verify your turbo’s outlet before ordering.

Fitment Details

• Vehicle: 1989, 1990, 1991, 1992, 1993 Dodge Ram 2500/3500, 5.9L 12-valve Cummins, 2WD only.
• Configuration: 4" turbo-back, single side exit, 409 stainless steel.
• Turbo interface: HX40-style downpipe (for HX40-outlet aftermarket turbos).
• Cab/bed lengths: Supports all cab and bed lengths with included sections.

FAQs

WILL THIS FIT MY STOCK TURBO?

No. The K4209S-HX40 includes an HX40-flange downpipe designed for aftermarket HX40-outlet turbos. If you are on a stock first-gen turbo, choose a system with the correct stock-style outlet or add an appropriate downpipe.

IS THIS KIT 2WD OR 4WD?

This specific part number is for 2WD (2x4) trucks. Diamond Eye offers separate part numbers for 4x4 applications.

WHAT MATERIAL IS USED?

409 stainless steel tubing for excellent durability and corrosion resistance.

DOES IT INCLUDE ALL HANGERS AND HARDWARE?

Yes. It is a direct-fit, bolt-on kit that reuses OE-style hangers with included hardware.

Cross-Reference / Alternatives (MBRP-only)

• For a comparable 2WD 4" turbo-back system in aluminized steel: MBRP S6148AL.
• For 4WD first-gen alternatives (non-HX40, different fitment): MBRP S6150AL, MBRP S6150PLM.

Specifications