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AMSOIL Hydraulic Oil
Synthetic formulation delivers the ideal combination of excellent biodegradability and wear protection for mobile and stationary hydraulic applications
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| Product code | Package size | Unit of measure |
|---|---|---|
| BHO05-EA | 5 Gallon Pail | Each |
| BHO55-EA | 55 Gallon Drum | 55 Gallon Drum |
AMSOIL ISO 46 100% Synthetic Biodegradable Hydraulic Oil (BHO) is a saturated synthetic ester fluid engineered for mobile and stationary hydraulic systems operating in environmentally sensitive areas. The ISO VG 46 grade is the most common worldwide multi-season viscosity for outdoor construction, forestry, marine and turf equipment, and the synthetic ester base chemistry pairs readily biodegradable performance with the wear protection demanded by gear, vane and piston pumps under high pressure and high temperature.
Vegetable-based environmentally acceptable lubricants typically deliver biodegradability at the expense of oxidation stability, cold-weather flow, and seal life. The Biodegradable Hydraulic Oil formulation uses saturated synthetic ester base stocks paired with ashless, non-zinc additive chemistry to avoid that trade-off, holding viscosity across a wide operating range while keeping the molecule biologically degradable in soil and water.
The fluid is compatible with most synthetic and petroleum-based hydraulic oils, but mixing dilutes the EAL classification and shortens service life. Drain and flush the reservoir before installation to preserve the readily biodegradable certification and the warranty coverage.
Premium synthetic ester base oils and a balanced anti-wear package form a resilient lubricating film on pumps, motors, valves and cylinders, holding up under the shock loading and elevated temperatures common in construction and forestry hydraulics. Bench testing reports a 0.48 mm wear scar on the Four-Ball Wear Test (ASTM D4172, 40 kg, 1200 rpm, 75 degrees C, 60 minutes), and the formulation passes the ASTM D7043 Vane Pump Test and reaches a Failure Load Stage of 12 on the FZG gear test (ASTM D5182).
Biodegradable Hydraulic Oil carries a Pw1 environmental persistence classification, the fastest and highest level of biodegradation in the Swedish Standard scheme. Under the Modified Sturm test (OECD 301B), more than 75 percent of the fluid converts to carbon dioxide within 28 days, qualifying it as Readily Biodegradable and as an Environmentally Acceptable Lubricant under the U.S. Vessel General Permit. In the event of a leak, ruptured line or minor spill near waterways or sensitive soil, the molecule breaks down quickly rather than persisting in the environment.
High-quality oxidation inhibitors slow the formation of varnish, sludge and acid in elevated-temperature service so long oil life is achievable in stationary reservoirs and continuously cycled mobile systems. Foam tendency on ASTM D892 measures 0/0 across Sequences I, II and III, supporting responsive, non-spongy hydraulic control. Copper strip corrosion (ASTM D130) rates 1A, and the fluid passes the ASTM D665 A and B rust tests on both distilled and salt water, protecting yellow metals and ferrous components alike.
The ester chemistry is compatible with common nitrile, hydrogenated nitrile, fluorocarbon and polyurethane seal materials used in modern hydraulic equipment, helping reduce leaks and extend seal life. Demulsibility on ASTM D1401 measures 40-40-0 in 15 minutes, releasing entrained water quickly so it can be drained from the reservoir before it reaches the pump.
Use Biodegradable Hydraulic Oil as a direct replacement for most synthetic and conventional ISO 46 hydraulic fluids in stationary and mobile gear, vane and piston systems operating under high pressure and high temperature. It is engineered for any application where a leak, spill or ruptured hose could release fluid into soil, surface water or groundwater, including construction near rivers and wetlands, logging and forestry equipment, farming and turf-care equipment, locks and dams, marine deck machinery, snow grooming and ski-area lift hydraulics, and vessels subject to U.S. EPA Vessel General Permit (VGP) requirements for environmentally acceptable lubricants.
Pair the fluid with a clean reservoir, a properly sized hydraulic filter, and a return-line breather rated to keep particulate and water within the OEM cleanliness target. Avoid blending aftermarket EP, anti-wear, or anti-foam additives; the formulation is balanced to meet the EAL specifications as supplied, and additional chemistry can disqualify it from VGP and EN 16807 status.
| Property | Value |
|---|---|
| ISO Viscosity Grade (ASTM D2422) | 46 |
| Kinematic Viscosity at 100 degrees C, cSt (ASTM D445) | 9.7 |
| Kinematic Viscosity at 40 degrees C, cSt (ASTM D445) | 47.6 |
| Viscosity Index (ASTM D2270) | 195 |
| Brookfield Viscosity at -30 degrees C, cP (ASTM D2983) | 4,300 |
| Specific Gravity (ASTM D1298) | 0.9182 |
| Density, lbs/gal (ASTM D1298) | 7.647 |
| Flash Point COC, degrees C (degrees F) (ASTM D92) | 302 (greater than 576) |
| Pour Point, degrees C (degrees F) (ASTM D97) | -43 (-45) |
| Four-Ball Wear, mm (ASTM D4172, 40 kg, 1200 rpm, 75 degrees C, 60 min) | 0.48 |
| Copper Strip Corrosion, 100 degrees C, 3 hr (ASTM D130) | 1A |
| Foam ASTM D892, Seq I, II, III, ml | 0/0, 0/0, 0/0 |
| Demulsibility (ASTM D1401) | 40-40-0 (15 min) |
| FZG Failure Load Stage (ASTM D5182) | 12 |
| Rust Procedure A and B (ASTM D665) | Pass |
| Conversion to CO2 in 28 days (OECD 301B) | Greater than 75 percent, Readily Biodegradable |
AMSOIL ISO 46 100% Synthetic Biodegradable Hydraulic Oil is available to order online in pails, drums, totes, and bulk quantities. Compare grades and chemistries in the ISO hydraulic oil guide, then Buy online
Standard mineral-oil hydraulic fluids are not readily biodegradable and persist in soil and water after a leak. Biodegradable Hydraulic Oil is built from saturated synthetic esters that convert more than 75 percent to carbon dioxide within 28 days on the Modified Sturm test (OECD 301B) and carry the Pw1 ultimate biodegradability rating, the fastest and highest classification under the Swedish Standard scheme.
An EAL is a lubricant that meets the U.S. EPA Vessel General Permit criteria for biodegradability, minimal aquatic toxicity, and non-bioaccumulation. Biodegradable Hydraulic Oil qualifies as an EAL and is appropriate for VGP-regulated equipment, deck machinery, stern tubes, controllable pitch propellers, and any hydraulic system that operates over or near surface water.
The fluid covers most ISO 46 service in gear, vane and piston pump systems on construction equipment near waterways, forestry and logging machines, lock-and-dam hydraulics, marine deck equipment, snow groomers and ski-area lifts, turf-care equipment, and any stationary reservoir where leakage could reach soil or surface water. Confirm reservoir cleanliness and seal compatibility before changeover.
The formulation is technically compatible with most synthetic and petroleum-based hydraulic oils, but mixing dilutes the EAL classification and shortens the readily biodegradable service life. Mixed reservoirs do not qualify for extended drain intervals and may lose VGP compliance. Drain and flush the system before installation.
It is an ISO Viscosity Grade 46 hydraulic oil, with a kinematic viscosity of 47.6 cSt at 40 degrees C and 9.7 cSt at 100 degrees C, a viscosity index of 195, and a pour point of -43 degrees C. The wide viscosity-temperature span supports year-round outdoor use without seasonal grade changes in most temperate climates.
No. Using AMSOIL synthetic lubricants does not void original equipment manufacturer warranties under the Magnuson-Moss Warranty Act when the fluid meets the OEM specification for the application. Biodegradable Hydraulic Oil meets DIN 51524 Part 2 and 3, ISO 15380 HEES and EN 16807 for hydraulic service. Match the OEM specification to the equipment manual.