What You're Actually Buying
This is the spin-on style water separator/fuel filter combo used on Detroit Diesel DD13 and DD15 engines, which covers a huge chunk of Freightliner Cascadias from 2008 up through current builds. It pulls water and sediment out of the fuel before it hits the high-pressure pump, which on these common-rail Detroit engines is not a part you want to skimp on.
The part sits in the same housing as your primary fuel filter setup, threaded on with a standard gasket seal. Detroit's been fairly consistent with this design across DD13/DD15 model years, but engine ECM software and fuel system revisions have changed a few times, so don't assume every Cascadia in the yard takes the same one.
We stock this as an aftermarket replacement — not a Detroit-branded part — built to the same spec and dimensions as the number stamped on your old filter.
Why These Numbers Cross
A0000905251 is the Detroit/Mercedes-Benz part number, and it cross-references to NAPA 600568, Donaldson P552709, and Fleetguard/Peterbilt FS20176FLG because all four are built around the same thread size, seal diameter, and micron rating for this application. Different filter manufacturers just slap their own part number on essentially the same spin-on canister.
Where guys get burned is assuming any water separator that physically threads on will work. Micron rating matters here — too coarse and you're not protecting the injectors, too restrictive and you're starving fuel flow under load. These four numbers are matched for media rating as well as fit.
Always pull the number off your old filter or check the truck's VIN before ordering. Detroit made minor spec changes over the DD13/DD15 production run, and a filter that fit a 2010 Cascadia isn't automatically right for a 2020.
Ordering From PartStop
We're in Tacoma and keep these in stock for same-day pickup or will to have it on your dock same-day if you're local. Ship nationwide if you're not.
At $49.99 this is a straightforward swap — no core charge, no drama, and it carries our standard 6+ month warranty against defects.
If you're not 100% sure which filter your DD13 or DD15 takes, call us with the VIN or bring in the old filter. Takes two minutes and saves you a return shipment.
A0000905251 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to A0000905251. Use them to identify the part — then confirm the exact fit by VIN or the number stamped on your old unit before you order. An interchange is a starting point, not a fitment guarantee.
| Brand / Line | Cross-Reference Numbers |
|---|---|
| NAPA | 600568 |
| Donaldson | P552709 |
| Fleetguard/Peterbilt | FS20176FLG |
Frequently asked questions
Does A0000905251 fit my 2016 Cascadia?
Likely yes if it's running a DD13 or DD15, but Detroit changed a few fuel system specs across model years. Give us the VIN or pull the number off the filter currently in the housing and we'll confirm before you order.
Is this the same as the Donaldson P552709?
Same fit, same micron rating, different manufacturer stamping. Donaldson P552709 cross-references directly to this application — we sell the aftermarket version, not Donaldson-branded, but it's built to the same spec.
How do I know if I need this or a different DD15 filter?
Check the number printed on your old filter housing first — that's the fastest way. If it matches or cross-references to A0000905251, NAPA 600568, or FS20176FLG, you're good. When in doubt, call us with the VIN.
Not sure it fits? We check before you pay.
Run your VIN and we’ll match parts to your exact truck, or call the counter — a person who knows trucks verifies fitment by OEM number before the order ships. No wrong-box returns.
More cross-reference guides
Need the part, not just the reading?
Every part below is a Premium Quality aftermarket Direct Replacement with published OEM cross-reference numbers, a 6+ month warranty and same-business-day shipping from Tacoma, WA. Not sure it fits? Run your VIN — or call and a person who knows trucks will verify fitment before you pay.