WIX Filters · 51xxx · return line
51680 filter element: specifications & equivalents
The 51680 is a WIX Filters return-line hydraulic filter element, built with wire/glass media, sized 118.6 × 288.2 mm OD × length, rated at 9 µm class. Verify against the current manufacturer data sheet before ordering.
Envelope OD × L 118.6 × 288.2 mm
Filtration rating 9 µm nom.
Media Wire/Glass
Thread 1 1/4-11 BSP
Collapse / burst 25.9 bar
Line type return
Catalog verified. Parameters extracted from the manufacturer’s electronic
catalog / official interchange document and checked 2026-09-28. Confidence score 0.90.
Specification table
| Parameter | Value |
|---|---|
| Filter type | return line |
| Media | Wire/Glass |
| Filtration rating | 9 µm |
| Rating basis | nominal |
| Outside diameter OD | 118.6 mm |
| Length | 288.2 mm |
| Thread / connection | 1 1/4-11 BSP |
| End caps | spin-on baseplate with attached gasket |
| Flow direction | outside-in |
| Collapse / burst pressure | 25.9 bar |
| Integral bypass valve | none (housing/valve-dependent) |
| Seal material | Nitrile (NBR) |
| Manufacturer part no. | 51680 |
| Source catalog | WIX Filters (MANN+HUMMEL): WIX Filters online product catalog |
| Last verified | 2026-09-28 |
Sources: WIX Filters (MANN+HUMMEL) — WIX Filters online product catalog — accessed 2026-09-26.
WIX Filters® and all model designations are trademarks of their respective owners, used here for identification only — ElementRef is an independent reference site, not an authorized WIX Filters distributor.
Dimensional drawing
Dimensions & series range
| Outside diameter | 118.6 mm (4.669 in) |
| Overall length | 288.2 mm (11.346 in) |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| ↔ A121C10 | Filtrec | partial | Filtrec's official Cross Navigator maps WIX 51680 to FILTREC A121C10 as a direct replacement, publishing the FILTREC element's OD/ID/height envelope and media grade. Rated micron differs (9 vs 10 µm) — verify efficiency class and collapse/seal for the housing before substituting. |
| ↔ HF6822 | Fleetguard | partial | Fleetguard's online catalog lists 51680 as an interchange for HF6822. 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.
Full chart: WIX Filters cross reference chart →
How the 51680 model number is decoded
- 51680WIX hydraulic spin-on filter part number.
- 1 1/4-11 BSPMounting thread: 1 1/4-11 BSP (spin-on baseplate).
- Wire/GlassFilter media: Wire/Glass.
Typical equipment & applications
- Mobile and industrial hydraulic return circuits
- Construction and agricultural equipment
- Heavy-duty transmission and torque-converter circuits
Selection pitfalls — read before you substitute
- Line type is not interchangeable: return-line cartridges are low-collapse executions that typically tolerate roughly 10–20 bar differential, while pressure-line elements are commonly rated 100–210 bar. Installing a low-collapse element in a pressure housing can rupture the media on cold-start spikes.
- This element has no integral bypass — opening pressure is set by the housing’s reusable bypass valve. Confirm the valve setting (commonly 3.4 bar) is present before fitting.
- “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.
- This execution uses nitrile (nbr) seals — verify the compound against the fluid data sheet: standard nitrile (NBR) can fail early in phosphate-ester fluids and at sustained high temperature, where 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 are the dimensions of the 51680 filter element?
The published envelope is 118.6 mm OD × 288.2 mm length (4.669 × 11.346 in). Confirm against the housing drawing before ordering.
What micron rating does 51680 use?
This element is rated 9 µm (nominal class). Always compare Beta ratings at the same test point: two brands may print different micron numbers for the same physical grade.
What replaces the 51680 filter element?
2 partial match(es) requiring parameter review
How do I read the 51680 part number?
See the designation decoder above: each segment of 51680 encodes size, line type, filtration grade and media/collapse execution.
Is a same-envelope aftermarket element always a drop-in replacement?
No. Matching OD and length only proves the cartridge fits the bowl. End-cap style, seal compound, micron/Beta rating, collapse pressure and bypass configuration must also match; the table above tags every equivalent as full, partial or verify for exactly this reason.
How often should a hydraulic filter element be replaced?
Replace at the housing manufacturer’s recommended differential-pressure setting (commonly signalled by a clogging indicator), or on a time-based service interval when no indicator is fitted — never wait for bypass to open continuously, because unfiltered oil then reaches the valves.
Other models in the 51xxx series
All 306 →Reviewed & verified by the ElementRef engineering desk against WIX Filters (MANN+HUMMEL) on 2026-09-28. Read our editorial & correction policy.