Cummins ISB 6.7 Aftertreatment Parts: ESN, ATSN and Emissions
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Quick answer: For ISB 6.7 aftertreatment parts, send the installed-engine ESN and control/emissions identity, vehicle application, aftertreatment serial number (ATSN), and the complete markings of the assembly or component needed. Identify whether the request concerns a DPF, DOC, SCR assembly, sensor or dosing component. Engine displacement alone does not identify the installed exhaust system. [1] [2] [5]
Application: Commercial ISB6.7 aftertreatment identification and parts requests. Examples use Cummins' February 2022 guide covering stated EPA 2013/2017/2021 arrangements, undated identifier/catalog references and 2014 B101 school-bus training. These sources do not establish a replacement for every ISB/B6.7, Ram pickup, later generation or altered installation.
Why are truck and emissions details needed as well as “ISB 6.7”?
Cummins' February 2022 reference guide 5676599 organizes aftertreatment by OEM, engine family, rating and emissions arrangement. It separates EPA 2013 SCR/DPF modular systems from the stated 2017 and 2021 single-module arrangements, and directs readers to the current catalog for up-to-date part information. [1]
That structure explains why a family name is only a starting point. Record the VIN, chassis make/model, installed-engine ESN and full control designation, emissions label and known replacements. Identify the emissions application from the actual records rather than guessing it from the truck's registration year.
Keep original-build information with the current component record. If the engine or aftertreatment was replaced, tell the parts provider; the installed assembly must be reconciled with the documented application before a replacement is selected.
What is the difference between an ESN, ATSN and part number?
The engine serial number identifies the engine. The aftertreatment serial number identifies an aftertreatment assembly. A part number identifies a part or service assembly; do not relabel it as a serial number.
Cummins' undated Digital Service Tools quick reference distinguishes ATSNs, CES-formatted part numbers and Cummins part numbers, including suffixes. It also points readers to physical identification on the existing assembly. Preserve each label's exact heading and complete value in your private request. [2]
| Record | What to send | What to clarify |
|---|---|---|
| Engine and vehicle | ESN, controls, VIN and emissions/application record. | What is installed and which application is being serviced? |
| Aftertreatment label | Complete ATSN and safely obtained photo with its heading visible. | Which assembly or section does the label identify? |
| Part marking | Full Cummins/CES marking, description and suffix. | Part number, serial number or another identifier? |
| Requested component | Exact name, position and diagnostic findings. | Complete assembly, service section, sensor or dosing item? |
Why do assembly names and sensor positions matter?
A DPF, DOC and SCR catalyst are different component names. The reference guide also distinguishes a top-level assembly from individual listed sections. Have the diagnosis and quote identify which level is actually required; “aftertreatment can” is too vague for a useful order. [1]
Cummins' 2014 B101 school-bus training gives a concrete, dated sensor example: its 2013 aftertreatment material distinguishes inlet and outlet NOx sensors, including connector keying and internal software, and identifies voltage-specific versions. This is evidence for preserving position and application, not a claim that those examples establish every later sensor's fitment. [4]
Include the exact sensor position named in the diagnostic and its complete markings. A visually similar probe or connector does not settle which part belongs in the confirmed application.
Can the engine record and aftertreatment label disagree or be incomplete?
Cummins' undated QuickServe catalog announcement describes searches using ATSN, CES part number or Cummins emissions part number. It explains that an ATSN may link to an ESN and that an ESN can be needed to narrow option details. Its switchback example also distinguishes DPF and SCR serial records. Treat those as lookup concepts; the old screen directions are not a promise about today's interface. [3]
The current Cummins parts-information page continues to list ESN, ATSN and part-number lookup inputs. [5] If a label is unreadable or a lookup is ambiguous, tell the provider which identifier is missing. Ask for help identifying the installed assembly and any replacement history. Do not complete a number by guessing characters or assume a catalog result proves an undocumented swap is correct.
What should the quote and repair plan confirm?
Send the complete identity record with the diagnosed component and the supporting fault/test report. A derate or frequent-regeneration complaint describes behavior; the parts request should explain which component the diagnosis actually identified.
Ask the quote to confirm the exact application, whether it supplies a complete assembly or service section, included sensors/hardware/seals, and any required installation, setup and repair verification. Ask about order-specific core-return terms if a remanufactured item is being considered.
Send the engine and aftertreatment identities together
Use ATP's part-fitment request with label photos and the diagnosed part. Fitment, package contents and availability require confirmation. For a separate coolant complaint, use the ISB 6.7 EGR/coolant-loss guide.
Common ISB 6.7 aftertreatment-parts questions
Is the engine serial number the same as the ATSN?
No. Keep engine and aftertreatment identifiers in separately labeled fields with the original label photos.
Will one DPF fit every commercial ISB 6.7?
The cited guide distinguishes OEM, engine and emissions arrangements. Confirm the installed assembly through current lookup.
Can inlet and outlet NOx sensors be chosen by appearance?
The dated B101 training explicitly distinguishes those positions and application details. Match the diagnosed position and current part information.
What if the aftertreatment was replaced before I bought the truck?
Send the current labels and the engine/vehicle record together. Have the provider reconcile the installed hardware rather than relying only on original-build details.
Does this guide confirm a part number, stock or regeneration repair?
No specific order or repair is confirmed here. Obtain the diagnosis and application confirmation before selecting parts.
Technical sources and application notes
These primary manufacturer documents support the stated examples. Dated bulletins explain diagnostic distinctions; the current service information for your engine controls the repair. ATP prepared this editorial guide; no independent technician review is claimed.
- Cummins, Genuine Cummins Aftertreatment Systems Part Number Reference Guide, bulletin 5676599, printed February 2022. EPA 2013 modular and 2017/2021 single-module scope; current lookup required. No part-number rows reproduced.
- Cummins Digital Service Tools, Finding Aftertreatment Serial & Part Numbers. Undated three-page quick reference; identifier and assembly examples, checked November 2, 2026.
- Cummins QuickServe, Cummins Emission Solutions Catalog Now Available. Undated catalog announcement; ATSN/CES lookup and ESN-linkage explanation, checked November 2, 2026. Interface instructions are historical.
- Cummins, ISB6.7 CM2350 B101 for School Bus Applications, 2014 training deck. EGR/cooling slides 43 and 46-50; separately scoped 2013 aftertreatment/sensor examples. Manufacturer presentation public copy hosted by Studylib.
- Cummins, Parts Information. ESN/ATSN catalog lookup and engine-identification/manual guidance; checked November 2, 2026.
