Restore emissions performance with this premium Skyline aftermarket Cummins 5509698 / 4394855 Diesel Oxidation Catalyst (DOC) Replacement Inlet Module. This brand-new unit serves as a direct alternative to OEM part numbers 5509698, 4394855, A055N645, 4394756, A055J297, 5509698NX, 5509698RX, 4394855NX, 4394855RX, 4394756NX, and 4394756RX. Engineered as an exact-fit replacement for heavy-duty Class 8 commercial vehicles powered by Cummins X15, Cummins X12, and EPA21 15-liter ISX/QSX diesel engines, it requires no exhaust system modifications for installation, carries zero core charge, and ships free within the continental United States.

Cummins 5509698 / 4394855 Cross Reference

How to Verify Your Unit: This direct-fit particulate filter replaces exhaust components stamped with housing, casting, or manufacturing tags matching any of the interchangeable assembly numbers or supplier cross-references listed below:

Choose Your Kit Configuration

Select the setup from the product options above that best fits your shop's needs:

• Full Kit (Best Value): Includes (1) Brand-New DOC, (1) 2880215 inlet gasket, (1) 5304868 primary gasket, (1) 2880213 clamp, and (1) 5304849 clamp.
• DOC Only: Includes the replacement DOC catalyst only. Installation gaskets and clamps are not included.

Key Features & Specifications for Part 5509698 / 4394855

• Proudly Built in the USA: Designed, engineered, and manufactured in America.
• No Core Charge: Brand-new aftermarket component; eliminates core return hassle and freight delays.
• Exact-Fit™ Technical Dimensions: Engineered with OEM-matching technical specifications, pre-machined sensor ports, and rigid alignments for straight exhaust execution with zero exhaust system modifications required.
• Substrate Performance Matrix: Advanced flow-through wall-flow precious metal washcoat core substrate ensures precise regeneration intervals and long-term particulate collection reduction.
• Industry-Leading Warranty: Backed by a 3-year unlimited mileage warranty on all Skyline aftermarket solutions.
• EPA Compliant: Meets federal emissions standards for applicable particulate matter reduction requirements.
• Free Shipping: Free ground shipping within the continental United States. Orders placed before 2:00 PM Eastern ship out the same business day.

Cummins 5509698 / 4394855 Vehicle Fitment Guide

Direct alternative solution for commercial heavy-duty Class 8 vehicles configured with compatible exhaust setups from approximately 2017 to present models. Optimized for:

• Engine Platforms: Cummins X15, Cummins X12, and EPA21 15-liter ISX/QSX diesel engine variants deployed across major vocational, motorcoach, and heavy-duty chassis fleets.
• Chassis Fitments: This specific high-traffic physical layout matches frame attachments across major line-haul and vocational operations:
  • Peterbilt Platforms: Heavy conventional and severe-duty vocational configurations including models 389, 567, and 579.
  • Kenworth Platforms: Over-the-road conventional and heavy utility models including T680, T880, and W900 setups.
  • Freightliner Platforms: Class 8 highway fleets including Cascadia and Coronado fleets.

Compatible OEM Master Assembly Numbers: 4387636, 4387637, 5508391, 5508392, 5508458, 5508564, 5508565, 5508566, 5508613, 5509118, 5509119, 5509158, 5509159, 5509160, 5509163, 5509164, A052T699, A052T700, A062R486, A062R527, A062R531, A062R592, A062R607, A062R609, A062R613, A062R615, A063G419, A063G420, A063G425, A063G434, A063G435, A063G437, A063G438

Signs Your Cummins DOC Needs Replacement

• Unexplained increases in active downstream DPF regeneration cycles linked to unburnt fuel face-loading
• Active dashboard diagnostic trouble codes (DTCs) signaling low DOC catalyst efficiency or temperature out-of-range parameters matching 5509698 / 4394855
• Upstream oil or fuel face-plugging caused by recent turbocharger seals failing or engine injector washing failures
• Unexplained commercial engine backpressure increases or gradual exhaust system power loss

*Note: Always verify exact vehicle compatibility using your vehicle's VIN number, emissions family descriptor tag, or the original stamped OEM part number on your filter unit casing before placing an order.

Disclaimer: Product images for reference only. Final replacement hardware items matching OEM 5509698 / 4394855 such as gaskets, clamps, and sensor ports depend on your kit configuration. Selecting the "Full Kit" option adds the explicitly listed installation components to your shipment.