Cummins ISC/ISL (2003-16) “4955485NX” EGR Cooler

Precision Remanufacturing for Heavy-Duty ISC & ISL EnginesThe Cummins 4955485NX EGR Cooler is remanufactured by Turbo Kings to restore OEM cooling performance and structural integrity for 2003–2016 Cummins ISC and ISL engines. These engines power a wide range of medium and heavy-duty trucks, buses, and vocational equipment—where cooling reliability directly impacts uptime.Each core undergoes complete disassembly and internal inspection to identify fatigue, cracking, or restricted flow passages. The cooler housing and internal fin assemblies are first treated in a heated alkaline detergent system, designed to dissolve thick soot, carbon, and oil residue without eroding internal brazing or stainless surfaces. This step restores full flow through both coolant and exhaust channels, eliminating hotspots caused by soot restriction.After the detergent flush, each core enters a 48-hour mild acid bath made from a balanced citric- and phosphoric-acid blend. This controlled descaling removes oxidation, mineral scale, and coolant corrosion that form over years of service. Each housing is then chemically neutralized to halt the acid reaction and prevent flash corrosion.If the inspection reveals any pinholes, cracks, or distortion, the cooler is TIG-weld re-fabricated using stainless filler matched to Cummins OEM metallurgy. Our alignment jigs ensure correct geometry so the cooler seats precisely to factory gaskets during reinstallation. Every finished assembly is then pressure tested to 125 PSI, fully submerged, verifying zero cross-leakage between the coolant and exhaust sides.What Makes a Turbo Kings Rebuild DifferentTurbo Kings’ EGR rebuilds are performed using the same industrial-level chemistry and validation standards that OEMs rely on. Our alkaline detergent process cleans deeper than solvent or spray rinses, flushing out oil carbon residue from both ends of the fin stack. The 48-hour acid soak is strictly time-controlled—strong enough to clear scaling, yet safe for weld seams and thin-walled tubing.Following treatment, each cooler is neutralized, air-purged, and oven-cured to eliminate any trace of moisture. The TIG-weld restoration stage rebuilds fatigued sections to withstand repeated heat cycling, preventing common stress fractures seen in high-hour ISC/ISL units.Before final approval, technicians verify flatness of sealing flanges, surface finish, and port alignment, ensuring every cooler is ready for direct bolt-on installation. No cooler leaves the facility without passing Turbo Kings’ 125 PSI hydrostatic pressure test.Why Fleets and Owner-Operators Trust Turbo KingsTurbo Kings is known for consistent quality, fast turnaround, and reliability tested in the field. Our EGR coolers are built for fleets that expect OEM performance without downtime.OEM Fitment Guarantee – Direct replacement for Cummins ISC & ISL 2003–2016 applicationsPressure Tested to 125 PSI – Guarantees leak-free coolant/exhaust isolationCorrosion-Free Finish – Neutralized and oven-cured post-descalingWeld-Reinforced Durability – TIG-repaired and geometry-verifiedWarranty: 6 Months / Unlimited MileageEach unit is serialized and certified for performance before leaving the Turbo Kings reman facility.Our Process at a GlanceDisassembly & Inspection – Detect cracks, wear, and cloggingHot Alkaline Flush – Removes oil, soot, and carbon buildup48-Hour Acid Descale – Clears oxidation and coolant scaleTIG-Weld Repair – Rebuilds structural fatigue or porosityPressure Test (125 PSI) – Submerged validation for cross-leaksNeutralization & Oven Drying – Ensures corrosion-free internals