Fleetguard · HF Hydraulic · return line
HF6778 filter element: specifications & equivalents
The HF6778 is a Fleetguard return-line hydraulic filter element, sized 128.93 × 272.01 mm OD × length. Verify against the current manufacturer data sheet before ordering.
Envelope OD × L 128.93 × 272.01 mm
Thread 1.00 1/2-16 UN-2B
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.
Specifications and cross-references are taken from the Fleetguard online catalog API. Where both TWA and Beta ratings are published the conventions differ — verify cleanliness targets, collapse rating and seal configuration against the current Fleetguard data sheet before ordering.
Specification table
| Parameter | Value |
|---|---|
| Filter type | return line |
| Outside diameter OD | 128.93 mm |
| Length | 272.01 mm |
| Thread / connection | 1.00 1/2-16 UN-2B |
| End caps | spin-on baseplate with attached gasket |
| Flow direction | outside-in |
| Integral bypass valve | none (housing/valve-dependent) |
| Manufacturer part no. | HF6778 |
| Source catalog | Cummins Filtration / Fleetguard: Fleetguard online product catalog (fleetguard.com) |
| Last verified | 2026-09-28 |
Sources: Cummins Filtration / Fleetguard — Fleetguard online product catalog (fleetguard.com) — accessed 2026-09-28.
Fleetguard® and all model designations are trademarks of their respective owners, used here for identification only — ElementRef is an independent reference site, not an authorized Fleetguard distributor.
Dimensions & series range
| Outside diameter | 128.93 mm (5.076 in) |
| Overall length | 272.01 mm (10.709 in) |
All 129×272 mm interchange elements →
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
|
↔ 100181001 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 100181001 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 167500H6LL205SP page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 167500H6LL205SP as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 180MA005BN page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 180MA005BN as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 1849 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 1849 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 1983188 page in verification queue | UFI | partial | Fleetguard's online catalog lists 1983188 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 2FR316 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 2FR316 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 3I0698 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 3I0698 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 3I0701 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 3I0701 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 40203 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 40203 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 4696671 page in verification queue | UFI | partial | Fleetguard's online catalog lists 4696671 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 51608503 page in verification queue | UFI | partial | Fleetguard's online catalog lists 51608503 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ 51849 | WIX Filters | partial | Fleetguard's online catalog lists 51849 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 59879221 page in verification queue | UFI | partial | Fleetguard's online catalog lists 59879221 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 70178 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 70178 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 750086UM page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 750086UM as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 7631729 page in verification queue | UFI | partial | Fleetguard's online catalog lists 7631729 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 85849 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 85849 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 9157907 page in verification queue | UFI | partial | Fleetguard's online catalog lists 9157907 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 92849 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 92849 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ 929445 | Parker | partial | Fleetguard's online catalog lists 929445 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 9327086 page in verification queue | UFI | partial | Fleetguard's online catalog lists 9327086 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 9U6983 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 9U6983 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ 9U6984 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists 9U6984 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ A09A10G page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists A09A10G as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ A152G06 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists A152G06 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ A177614 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists A177614 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ AG710202 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists AG710202 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ AG715586 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists AG715586 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ ARH0875LB05 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ARH0875LB05 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ BT8308-MPG | Baldwin Filters | partial | Fleetguard's online catalog lists BT8308MPG as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ BT8308-MPG | Baldwin Filters | partial | Baldwin's Form 561 Number-Finder cross-reference lists HF6778 (FLEETGUARD) as replaced by Baldwin BT8308-MPG. Form/fit listing without published performance data — verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ CGS150A06A page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CGS150A06A as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ CSG150A06 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CSG150A06 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ CSG150A06A page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists CSG150A06A as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ ESF22NFB page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ESF22NFB as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ F4E070HCB page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists F4E070HCB as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ FPE7005G page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists FPE7005G as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ H306W page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists H306W as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HC7500SDN8H page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7500SDN8H as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HC7500SKN8H page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7500SKN8H as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HC7500SKN8Z page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7500SKN8Z as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HC7500SUN8H page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7500SUN8H as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HC7937 page in verification queue | Pall | partial | Fleetguard's online catalog lists HC7937 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ HF0677800 page in verification queue | Fleetguard | partial | Fleetguard's online catalog lists HF0677800 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ MFE160105BN2 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists MFE160105BN2 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ P165978 page in verification queue | Donaldson | partial | Fleetguard's online catalog lists P165978 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ P562208 page in verification queue | Donaldson | partial | Fleetguard's online catalog lists P562208 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ P7254 page in verification queue | Donaldson | partial | Fleetguard's online catalog lists P7254 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ PR3962 page in verification queue | Parker | partial | Fleetguard's online catalog lists PR3962 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ R750H0806A page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists R750H0806A as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ SBF75008S3B page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists SBF75008S3B as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ SBF-7500-8Z5B | Schroeder Industries | partial | Fleetguard's online catalog lists SBF75008Z5B as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ SF-6707-MG | STAUFF | partial | Fleetguard's online catalog lists SF6707MG as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ SF-6731-MG | STAUFF | partial | STAUFF Filter Interchange lists HF 6778 (FLEETGUARD / CUMMINS) as replaced by SF-6731-MG. Envelope dimensions are published; media grade and performance data are not — confirm before substituting in cleanliness-critical circuits. |
|
↔ ST2870 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists ST2870 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ TT75S83B page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists TT75S83B as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ TT75S86B page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists TT75S86B as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ VOE11841688 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists VOE11841688 as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ WD13006X | MANN-FILTER | partial | MANN-FILTER's online catalog lists HF6778 (FLEETGUARD/CUMMINS FILTRATION) as a comparison number for WD13006X. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
| ↔ WD13007X | MANN-FILTER | partial | Fleetguard's online catalog lists WD13007X as an interchange for HF6778. Envelope cross-reference; verify micron grade, collapse rating and seal configuration before substituting. |
|
↔ WGPN7508 page in verification queue | Aftermarket | partial | Fleetguard's online catalog lists WGPN7508 as an interchange for HF6778. 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 HF6778 model number is decoded
- HF6778Fleetguard HF-series hydraulic spin-on filter part number.
- 272.01 mmOverall height.
- 128.93 mmLargest outside diameter.
- 1.00 1/2-16 UN-2BSpin-on mounting thread.
Typical equipment & applications
- Construction, agricultural and industrial hydraulic circuits
- Mobile-equipment hydraulic return and pressure lines
Selection pitfalls — read before you substitute
- A return-line element is not a pressure-line element: return cartridges (BN4HC low-collapse) tolerate roughly 20 bar differential, while BH4HC pressure executions are rated to 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.
- 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 are the dimensions of the HF6778 filter element?
The published envelope is 128.93 mm OD × 272.01 mm length (5.076 × 10.709 in). Confirm against the housing drawing before ordering.
What replaces the HF6778 filter element?
61 partial match(es) requiring parameter review
How do I read the HF6778 part number?
See the designation decoder above: each segment of HF6778 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 return-line 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.
Same-envelope elements from other brands
View full interchange →These 18 catalog element(s) share the 129×272 mm envelope. Envelope match alone does not guarantee interchangeability — compare micron/Beta, seals and collapse rating.
Other models in the HF Hydraulic series
All 2621 →Reviewed & verified by the ElementRef engineering desk against Cummins Filtration / Fleetguard on 2026-09-28. Read our editorial & correction policy.