FITMENT:
Compatible with Caterpillar Inc. diesel engines equipped with SCR emission systems (24V heavy-duty applications).

OEM reference number: 441-5128.
Used in diesel exhaust aftertreatment system for NOx monitoring (DEF/AdBlue SCR system).
Installed in exhaust system (inlet or outlet position depending on engine and aftertreatment layout).
Fitment must be confirmed by OEM part number and engine emission system configuration before installation.

FAQ:

Q1: How do I confirm compatibility?
A1: Match OEM number 441-5128 with your original sensor and verify connector type, voltage (24V), and SCR system configuration.

Q2: Where is this NOx sensor installed?
A2: It is installed in the SCR exhaust aftertreatment system of Caterpillar diesel engines, either upstream or downstream depending on configuration.

Q3: What are common failure symptoms?
A3: Engine warning light, SCR/DEF system fault codes, incorrect NOx readings, or reduced engine performance.

Q4: Is this compatible with all CAT engines?
A4: No, compatibility depends on engine model and emission system configuration. OEM number must be matched exactly.

Q5: Does replacement require programming?
A5: Some machines require system reset or diagnostic adaptation after installation.