Fuel Filter FF021 — Fuel Water Separator for Cummins ISX15 (Fleetguard FS20121) 132

Steinberg

Fuel Water Separator FF021 for Cummins B6.7 / L9 (2020+): FS20121 Cross-Reference

Name: Fuel Water Separator FF021 for Cummins B6.7 / L9 (2020+): FS20121 Cross-Reference
Brand: Steinberg
SKU: FF021
Price: 49.11 USD
Availability: InStock

SKU: FF021OEM: 5444245Cross: FS20121, 5444245, 5521648, ...

Confirmed Vehicle Compatibility

Freightliner M2 106 (Cummins B6.7, 2020+)Freightliner Cascadia (Cummins B6.7, 2020+)

Freightliner 114SD (Cummins L9, 2020+)Blue Bird Vision (Cummins B6.7, 2020+)

$49.11

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OEM-grade certified

30-day returns

Thread Size

1-14 UNS

Outer Diameter

94mm

Height

248mm

Filter Media

Synthetic (10 micron)

OEM Reference

5444245

Cross Reference

FS20121, 5444245, 5521648, 5528103, BF46266

Freightliner M2 106 (Cummins B6.7, 2020+)Freightliner Cascadia (Cummins B6.7, 2020+)Freightliner 114SD (Cummins L9, 2020+)Blue Bird Vision (Cummins B6.7, 2020+)

Not sure about your truck? Contact us with your make, model and year — we'll confirm compatibility within 1 business day.

Prepare & Safety First

Park on level ground, engage parking brake. Allow engine to cool for at least 30 minutes. Have drain pan and proper tools ready.

Remove Old Filter

Use a filter wrench to loosen and remove the existing filter. Let residual fluid drain completely into your pan.

Prep New Filter

Apply a thin coat of clean oil or fuel to the new filter's gasket seal. This ensures a proper, leak-free seal.

Install & Torque

Thread the new filter on by hand until gasket contacts, then tighten 3/4 to 1 full turn. Do NOT over-torque.

Start & Verify

Start the engine and let it idle for 2–3 minutes. Check for leaks. Check fluid level and top off if needed.

Download Full Installation PDF →

About This Filter

The Steinberg FF021 is a spin-on fuel water separator engineered for Cummins B6.7 and L9 engines meeting Stage V/EPA2020 standards (2020 and newer). Using synthetic coalescing media, it removes water and fine particulate contamination from diesel fuel before it reaches the high-pressure common rail injection system.

Carries Cummins OEM part number 5444245 and is a direct replacement for Fleetguard FS20121. Extended service intervals up to 1,000 hours. Replace at each PM service interval.

Compatible Part Numbers

Fuel Water Separator FF021 for Cummins B6.7 / L9 (2020+): FS20121 Cross-Reference (SKU: FF021) is a direct replacement for the following OEM and aftermarket part numbers:

FS20121544424555216485528103BF46266

OEM Reference Number

The OEM reference number for this filter is 5444245. Use this number to verify fitment with your truck manufacturer's parts catalog.