Keep clean fuel moving to the engine with the Wix Fuel Filter 33966NP, a secondary-position filter that strains dirt, rust, and other contaminants out of the fuel before they reach the fuel system. It fits a wide range of medium- and heavy-duty applications, including the 2000-2013 and 2015 Ford F-650 and F-750, 2007-2016 Freightliner M2 106, 2013-2016 Kenworth K270, 2008-2013 Peterbilt 210, and 2007-2017 Blue Bird Vision School Bus — see the "Vehicles it fits" section for the full list of 50 applications.
- Secondary filter: installs in the secondary (downstream) fuel-filtering position for this part type.
- Contaminant control: traps particulate that can otherwise reach and wear fuel-system components.
- Direct-fit replacement: a drop-in service part for the listed applications.
If a clogged or restricted secondary fuel filter is behind hard starting, hesitation, or reduced power, this replaces it as part of routine fuel-system maintenance.
Interchange: 201450304 · BF7940 · 86966 · 4934845 · P10715 · FF5632 · FF5812 · 317160 · FF1174 · H374WK · 333F6607 · LFF5632 · WK9037X · 3966NP · F65942 · 1000-FF33966 · 1000FF33966 · FF33966 · RCFF33966. Manufacturer part number 33966NP.
This part cross-references / interchanges with the following part numbers:
201450304, BF7940, 86966, 4934845, P10715, FF5632, FF5812, 317160, FF1174, H374WK, 333F6607, LFF5632, WK9037x, WK9037X, 3966NP, DF30165NN, F65942, 1000-FF33966, FF33966, RCFF33966, BH8101, 33966NP
Frequently Asked Questions
What does this fuel filter do?
It strains dirt, rust, and other contaminants out of the fuel before they reach the fuel system, helping protect downstream components during normal operation.
Where does the 33966NP install?
It is a secondary-position fuel filter, meaning it serves the secondary (downstream) fuel-filtering position for this application.
Will this fit my truck or bus?
It covers 50 applications across Ford, Freightliner, Kenworth, Peterbilt, Blue Bird, Autocar, IC Corporation, and Sterling. Check the "Vehicles it fits" section to confirm your exact year, make, and model.
What are signs the filter may need replacing?
Hard starting, hesitation, or reduced power can indicate a clogged or restricted filter. Diagnose the cause first; if the secondary filter is the issue, this replaces it.
What numbers does this filter interchange with?
It cross-references 201450304, BF7940, 86966, 4934845, P10715, FF5632, FF5812, 317160, FF1174, H374WK, 333F6607, LFF5632, WK9037X, 3966NP, F65942, 1000-FF33966, FF33966, and RCFF33966.
