AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil
Formulated with advanced synthetic technology to protect hydraulic systems from wear, rust, and oxidation. Designed for high-pressure, high-load and heavy-duty operations, ensuring smooth performance and long-lasting protection. Superior cold-weather fluidity allows for immediate flow, reducing strain on equipment and improving productivity.
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Product data sheets
View, download, or save a copy of the Product Data Sheet or Safety Data Sheet for AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil.
AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil
AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil (AWI) is the heavy-end industrial anti-wear viscosity in the AW Series, built for hot-running, high-pressure hydraulic systems in large-bore industrial presses, paper-mill hydraulics, plastic injection molders, machine tools, and large mobile equipment in summer or hot-climate use. A synthetic base oil system, a zinc-based anti-wear additive package, and a viscosity index of 188 deliver wear protection, oxidation resistance, and stable viscosity across a wide temperature window.
Anti-wear protection for high-pressure systems
Hydraulic pumps, vanes, valves, and piston elements operate in a high-pressure environment where the lubricant film carries the load. AWI is fortified with zinc-based anti-wear additives that protect pumps, motors, and valves against scuffing and adhesive wear. The Four-Ball Wear Test (ASTM D4172, 40 kg, 1200 rpm, 75 C, 60 min) records a 0.45 mm scar for the ISO 46 grade. The fluid passes Vickers M-2950-S and I-286-S vane-pump wear testing and is approved for Denison HF-0, HF-1, and HF-2 service.
Oxidation resistance and varnish control
Hot operation drives oxidation, and oxidation drives varnish, sludge, and acid buildup that foul servo valves and shorten fluid life. The synthetic base oils in AWI resist chemical breakdown, and the additive system fights acid formation through extended hot service. The ISO 46 grade carries a flash point of 230 C (446 F) and a fire point of 250 C (482 F) (ASTM D92), with a Copper Strip Corrosion result of 1A (ASTM D130) for yellow-metal compatibility.
Cold-start flow and viscosity stability
Wax-free synthetic base oils keep the formula fluid in sub-zero temperatures for outdoor equipment that sits overnight and starts under load. The ISO 46 grade carries a pour point of -46 C (-51 F) (ASTM D97) and a viscosity index of 188 (ASTM D2270), retaining film strength in summer heat without sluggish cold-start behavior. Kinematic viscosity is 49.1 cSt at 40 C and 9.7 cSt at 100 C (ASTM D445), inside the ISO VG 46 band (ASTM D2422).
Water separation, foam control, and rust protection
Hydraulic systems pick up water from condensation, washdown, and process leaks, and entrained water destroys hydraulic film. AWI demulsifies cleanly with a 40/40/0 result in 10 minutes (ASTM D1401), so free water separates and can be drained from the reservoir. The fluid passes ASTM D665 A and B rust testing in fresh water and synthetic sea water, and foam reading is 0/0 in all three sequences of ASTM D892.
OEM and industry specifications
The ISO 46 grade meets a long list of OEM hydraulic specifications used by industrial press, vane pump, and mobile equipment builders. Approvals for AWI include Vickers I-286-S and M-2950-S, Denison HF-0, HF-1, and HF-2, Cincinnati Milacron P-70, U.S. Steel 127 and 136, Racine variable volume vane pumps, DIN 51524 Part 2, AFNOR E 48-603, Ford M6C-32, GM LH-04-1, LH-06-1, and LH-15-1, Lee Norse 100-1, Jeffrey No. 87, BF Goodrich 0152, and Commercial Hydraulics. Confirm the exact specification required by the equipment manufacturer before changing fluid.
Recommended applications and service intervals
AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil is recommended for high- and low-pressure gear, vane, and piston hydraulic systems, both stationary and mobile, that call for any of the OEM specifications above. The ISO 46 grade is the heavy-end industrial AW viscosity, suited to hot ambient operation, large-bore industrial presses, paper-mill hydraulics, plastic injection molders, and large mobile hydraulic equipment in summer service.
Industrial: hydraulic presses, plastic injection molders, paper-mill hydraulics, machine tools, and stationary power units in normal or elevated ambient temperatures.
Mobile: large hydraulic systems on heavy equipment in summer or hot-climate use, including dump trailers, log splitters, and gear, vane, or piston hydraulics that specify an ISO 46 anti-wear fluid.
Severe service: extended drain and high-temperature duty cycles; oil analysis is recommended to maximize and verify intervals.
Excluded: phosphate-ester, silicone, and water-based hydraulic fluids; PM-500 series silver-containing pumps requiring R&O-only additive systems under AFNOR E 48-603 and Commercial Hydraulics references.
The formula is compatible with hydraulic system seals, petroleum hydraulic oils, and most synthetic hydraulic oils, but mixing dilutes the additive package and reduces performance benefits. For best results, drain and, if warranted, clean the system before refilling. Aftermarket fluid additives are not recommended.
Demulsibility, oil/water/cuff in 10 min (ASTM D1401)
40/40/0
Rust Test, fresh and synthetic sea water (ASTM D665 A and B)
Pass
Order AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil
AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil is available in 5 gallon pail (AWI05-EA), 55 gallon drum (AWI55-EA), and 275 gallon tote (AWI27-EA) sizes. AMSOIL industrial lubricants are backed by the AMSOIL Limited Warranty. To match the right ISO grade and AW versus R&O type for the system, work through the ISO Hydraulic Oil Guide and confirm application match against the AMSOIL Vehicle Lookup Guide, then order AMSOIL ISO 46 100% Synthetic Anti-Wear Hydraulic Oil.
My dump trailer lifted easier in colder temps, pump strained less
By Mark from Colorado on June 05, 2025.
Would recommend this to a friend.
Hydraulic oil
So far I am impressed . Test of time will be the deciding factor . This hydraulic oil fluid is totally different in appearance and viscosity from traditional Hydraulic oils. I have trusted Amsoil for 30 years and I use their oils in all my equipment , ( boat, mowers ,2 cycle etc.) If it uses oil it runs on Amsoil.
ISO 46 is a viscosity classification under ISO 3448, with a target kinematic viscosity near 46 cSt at 40 C. AWI tests at 49.1 cSt at 40 C (ASTM D445) and sits inside the ISO VG 46 band (ASTM D2422). The "AW" prefix indicates an anti-wear additive package, typically zinc-based, designed for high-pressure pump, vane, and piston hydraulic systems that need film strength under load.
Is AW 46 hydraulic oil the same as ISO 46?
AW 46 and ISO 46 describe different things on the same label. ISO 46 is the viscosity grade. "AW" identifies the fluid as an anti-wear formulation, typically zinc-based. AWI is both: an ISO VG 46 anti-wear hydraulic oil meeting Vickers I-286-S, Denison HF-0, HF-1, HF-2, and Cincinnati Milacron P-70. An R&O (rust and oxidation) ISO 46 oil shares the viscosity grade but lacks the AW additive package and is not interchangeable in pumps that require AW chemistry.
Is ISO 46 thicker than ISO 32?
Yes. ISO 46 has a higher kinematic viscosity at 40 C than ISO 32, so ISO 46 is the thicker fluid. ISO 32 is typically chosen for cold-climate or year-round mobile hydraulics, while ISO 46 is the heavy-end industrial AW grade for hot-running stationary systems and summer-duty mobile hydraulics. Match the grade the equipment manufacturer specifies for the system and operating temperature range.
Can ISO 32 and ISO 46 hydraulic oil be mixed?
AWI is compatible with petroleum hydraulic oils and most synthetic hydraulic oils, but mixing different ISO grades pushes the working viscosity out of the band the system was designed around. Drain the old fluid before refilling with the correct grade. Use oil analysis to verify operating viscosity if a partial mix cannot be avoided.
Is AMSOIL AWI a synthetic hydraulic oil?
Yes. AWI is a 100 percent synthetic anti-wear hydraulic oil. Naturally resilient synthetic base oils support a viscosity index of 188 (ASTM D2270) and a pour point of -46 C (-51 F) (ASTM D97). Conventional ISO 46 hydraulic oils typically run a lower VI and a higher pour point, which limits their cold-start flow and high-temperature stability.
Which fluids should not be replaced with AWI?
AWI is not compatible with phosphate-ester, silicone, or water-based hydraulic fluids. PM-500 series silver-containing pumps requiring an R&O-only additive system fall outside the AWI application range under the AFNOR E 48-603 and Commercial Hydraulics references. Confirm seal and pump compatibility against the equipment manufacturer specifications before converting.
Does using AMSOIL hydraulic oil affect equipment warranty?
No. Using AMSOIL synthetic lubricants does not void a new equipment manufacturer warranty, and AMSOIL industrial lubricants are backed by the AMSOIL Limited Warranty. Match the specification the equipment manufacturer requires, install the correct ISO grade, and keep records of fluid and filter changes.
