EXHAUST SYSTEM & COMPONENTS — 1989–1993 DODGE RAM 5.9L CUMMINS (12-VALVE)

Free up flow and protect your 1st-Gen’s turbo with CPP Diesel’s curated selection of turbo-back systems, downpipes, exhaust manifolds, elbows, clamps, V-band hardware, mufflers, stacks, and tips for the VE-pump 12-valve 6BT. Options in 4" and 5" to match your build and sound level.

Shop by Subcategory

• EXHAUST SYSTEMS (’89–’93) — 4"/5" turbo-back kits and hardware.
• DOWNPIPES — turbo outlet pipes for OE/HX40 and more.
• EXHAUST MANIFOLDS — 12V T3 manifolds, studs & gaskets.
• EXHAUST ELBOWS — elbows and adapters for custom routing.
• CLAMPS & ACCESSORIES — band clamps, hangers, hardware.
• V-BAND FLANGES & CLAMPS — HX40/S300/S400 connections.
• MUFFLERS & RESONATORS — quiet-tone and performance options.
• STACKS & ACCESSORIES — single/dual stack components.
• EXHAUST TIPS — polished and coated finishes.

Featured for 1st Gen

• Diamond Eye K4209A 4" Turbo-Back (’89–’93) — aluminized, value-packed.
• Diamond Eye K4209S 4" Turbo-Back Stainless (2WD) — corrosion-resistant.
• Diamond Eye 220099 Downpipe (’89–’93 2WD) — OE-style turbo outlet.
• 12V Exhaust Manifolds & Stud Kits — service or upgrade sealing.

Why Buy from CPP Diesel

• First-Gen Focus: Parts vetted for 1989–1993 VE-pump 12-valve trucks.
• Top Brands: Diamond Eye, MBRP, AFE, CPP in-house, and more.
• Expert Support: Help with downpipe fit, hanger layout, and material choice.
• Fast Shipping: Popular kits and hardware ship quickly from U.S. warehouses.

Explore the full 1989–1993 Cummins catalog for turbos, intercoolers, and fueling upgrades.

Helpful Notes

• 2WD vs 4WD: Some systems/downpipes are chassis-specific—check the product fit notes.
• ’91.5–’93 intercooled: Downpipe/elbow geometry differs from early trucks; verify turbo outlet (e.g., HX40).
• Material & sound: 409 stainless resists corrosion; longer mufflers/resonators reduce drone on long grades.
• Compliance: Select parts are labeled for off-road/competition where applicable—always follow local laws.
• Monitor temps: Pair with boost/EGT gauges to validate changes.

Frequently Asked Questions

4" vs 5" — which size should I choose?

4" fits most builds with minimal drone and great flow. 5" can reduce backpressure and lower EGTs on higher-power setups but may be louder and require more clearance.

Stainless or aluminized?

409 stainless offers better corrosion resistance; aluminized is cost-effective. Both perform when installed with quality clamps and hangers.

Will a turbo-back kit fit my lifted truck?

Yes, in most cases. Check shock/spring clearance and extend hangers as needed. Use band clamps and correct hanger angles to prevent rattles.

How do I cut interior drone?

Add a muffler or resonator, keep tailpipe length after the axle, and ensure all joints are sealed with proper band/V-band clamps.

Do I need a specific downpipe for HX40?

Yes—use an HX40-compatible downpipe/elbow and V-band. See Downpipes and V-Band parts.