Donaldson · Hydraulic Catalog · inline line
P550251 filter element: specifications & equivalents
The P550251 is a Donaldson inline-line hydraulic filter element, built with cellulose media, rated at 7 µm class. Verify against the current manufacturer data sheet before ordering.
OD/ID dimensions, collapse pressure and bypass settings are not printed in the filter-element choice table and are pending extraction from the housing dimension pages. Verify against the current Donaldson data sheet before ordering.
Specification table
| Parameter | Value |
|---|---|
| Filter type | inline line |
| Media | Cellulose |
| Filtration rating | 7 µm |
| Rating basis | nominal |
| Length | 271 mm |
| Integral bypass valve | none (housing/valve-dependent) |
| Manufacturer part no. | P550251 |
| Source catalog | Donaldson Company: Hydraulic Filtration Product Guide (F112100-ENG) |
| Last verified | 2026-09-28 |
Sources: Donaldson Company — Hydraulic Filtration Product Guide (F112100-ENG) — accessed 2026-09-27.
Donaldson® and all model designations are trademarks of their respective owners, used here for identification only — ElementRef is an independent reference site, not an authorized Donaldson distributor.
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| ↔ 927736 | Parker | partial | Parker ParFit interchange — Donaldson P550251 replaced by Parker 927736. Envelope match; verify grade and seals. |
| ↔ HF6711 | Fleetguard | partial | Fleetguard's online catalog lists P550251 as an interchange for HF6711. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ SBF-7500-810B | Schroeder Industries | partial | Schroeder online cross-reference (DONALDSON); envelope match — verify grade and seals. |
| ↔ WD13005X | MANN-FILTER | partial | MANN-FILTER's online catalog lists P550251 (DONALDSON) as a comparison number for WD13005X. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
Interchange levels: full catalog-confirmed drop-in · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the P550251 model number is decoded
- P550251Donaldson hydraulic filter element part number per the Hydraulic Filtration Product Guide (F112100-ENG).
- W023Product family: W023.
- CelluloseFilter media: Cellulose.
- 7 μmNominal filtration rating at βx(c) = 2 per ISO 16889.
Typical equipment & applications
- Donaldson W023 hydraulic filter housing
Selection pitfalls — read before you substitute
- “10 µm nominal” and “12 µm at β1000” can describe the very same media — one is reported at β≥200, the other at β≥1000 per ISO 16889. Compare ratings at the same Beta test point, not just the printed micron number.
- Nitrile (NBR) seals are standard for mineral hydraulic oil but fail early in some phosphate-ester fluids and at sustained high temperature; verify seal compound against the fluid data sheet (fluorocarbon/Viton executions may be required).
- End-cap geometry and the number/position of O-rings block interchange even when OD and length match — visually compare end caps before fitting, especially with aftermarket cartridges.
Frequently asked questions
What micron rating does P550251 use?
What replaces the P550251 filter element?
How do I read the P550251 part number?
Is a same-envelope aftermarket element always a drop-in replacement?
How often should a hydraulic return-line element be replaced?
Other models in the Hydraulic Catalog series
All 360 →Reviewed & verified by the ElementRef engineering desk against Donaldson Company on 2026-09-28. Read our editorial & correction policy.