ASTO 555
An advanced 5 mm2/s synthetic hindered ester oil incorporating a finely balanced blend of additives to improve thermal and oxidation stability¹ and to increase the load carrying ability of the base oil.
Features and benefits
Outstanding load carrying capacity
Corrosion and oxidation resistance
High thermal stability
Specifications & approvals
| Country / OEM | Specification |
|---|---|
| United States | DOD-PRF-85734A |
| British | DEF STAN 91-100 |
| NATO Code | O-160 |
| Joint Service Designation | OX-26 |
| Pratt & Whitney | 521C Type II |
| General Electric | D-50 TF 1 |
| Allison | EMS-53 (Obsolete) |
The TDS and MSDS are in English, but you can find these documents for other countries in the Shell EPC area
.
Applications
AeroShell Turbine Oil 555 was specifically developed to meet the high temperatures and load carrying requirements of supersonic transport (SST) engines and the DEF STAN 91-100 (formerly DERD 2497) and XAS-2354 specifications. AeroShell Turbine Oil 555 was also designed to give enhanced performance in current engines.
WIth the need to transmit more power and higher loads through helicopter transmission and gearbox systems (many helicopters use a synthetic turbine engine oil in the transmission/gearbox system), it has become apparent that the use of a very good load carrying oil, such as AeroShell Turbine Oil 555 is necessary. This in turn has led to the development of a U.S. Military Specification, DOD-PRF-85734, which covers a helicopter transmission oil against which AeroShell Turbine Oil 555 is fully approved.
AeroShell Turbine Oil 555 contains a synthetic ester oil and should not be used in contact with incompatible seal materials, and it also affects some paints and plastics.
Health, Safety and Environment
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Health and Safety
- This product is unlikely to present any significant health or safety hazard when properly used in the recommended application and good standards of personal hygiene are maintained.
- Avoid contact with skin. Use impervious gloves with used oil. After skin contact, wash immediately with soap and water.
- Guidance on Health and Safety is available on the appropriate Safety Data Sheet, which can be obtained from https://www.epc.shell.com/
Protect the Environment
- Take used oil to an authorised collection point. Do not discharge into drains, soil or water.
Additional information
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Versions
- AeroShell Turbine Oil 555 is also approved for use in the industrial and marine versions of the Rolls-Royce RB211-22 and Olympus engines, General Electric LM 100, 250, 350, 1500 and 2500 engines.
Advice
- Advice on applications not covered here may be obtained from your Shell representative.
Get in touch with us
We’re here to assist you with any inquiries or support you may need
Typical Physical Characteristics
| Properties | Method | DOD-PRF-85734A | Typical |
|---|---|---|---|
| Oil type | – | Synthetic ester | Synthetic ester |
| Kinematic viscosity @100°C mm²/s | ASTM D445 | 4.90 to 5.40 | 5.2 |
| Kinematic viscosity @40°C mm²/s | ASTM D445 | 23.0 min | 26.5 |
| Kinematic viscosity @-40°C mm²/s | ASTM D2532 | 13 000 max | 11 000 |
| Flashpoint (Cleveland Open °C Cup) | ASTM D92 | 246 min | 258 |
| Pourpoint °C | ASTM D97 | -54 max | <-60 |
| Total Acidity mgKOH/g | SAE-ARP-5088 | 0.75 max | 0.4 |
| Evaporation Loss 6.5 hrs @204°C % m | ASTM D972 | 10 max | 1.5 |
| Foaming characteristics ml | ASTM D892 | Must pass | Passes |
| Swelling of Standard Synthetic Rubber – SAE AMS 3217/1, 72 hrs @70°C | FED-STD 791 M.3604 and M.3433 | 5 to 25 max | 14 |
| Swelling of Standard Synthetic Rubber – SAE AMS 3217/4, 72 hrs @204°C | FED-STD 791 M.3604 and M.3433 | 5 to 25 max | 14 |
| Thermal Stability / Corrosivity 96 hrs – metal weight change @274°C, mg/cm2 | FED-STD-791 M.3411 | 4.0 max | Passes |
| Thermal Stability / Corrosivity 96 hrs – viscosity change, % | FED-STD-791 M.3411 | 5.0 max | 1.4 |
| Thermal Stability / Corrosivity 96 hrs – Total Acid Number Change, mgKOH/g | FED-STD-791 M.3411 | 6.0 max | 2.6 |
| Corrosion and Oxidation Stability 72 hrs, @175°C | FED-STD 791 M.5308 | Must pass | Passes |
| Corrosion and Oxidation Stability 72 hrs, @204°C | FED-STD 791 M.5308 | Must pass | Passes |
| Corrosion and Oxidation Stability 72 hrs, @218°C | FED-STD 791 M.5308 | Must pass | Passes |
| Ryder Gear Test, Relative Rating Hercolube A, % | FED-STD-791 M.6508 | 145 min | Passes |
| Bearing test rig, Type 1½ conditions – Overall deposit demerit rating, 100hrs | FED-STD-791 M.3410 | 80.0 max | Passes |
| Bearing test rig, Type 1 ½ conditions – Viscosity change @40°C, % | FED-STD-791 M.3410 | 0 to +35 | Passes |
| Bearing test rig, Type 1½ conditions – Total acid number change, mgKOH/g | FED-STD-791 M.3410 | 2.0 max | Passes |
| Bearing test rig, Type 1½ conditions – Filter deposits, g | FED-STD-791 M.3410 | 3 max | Passes |
| Sonic shear stability – viscosity change @40°C, % | ASTM D2603 | 4 max | 0.3 |
| Trace metal content ppm | ASTM D5185 or D6595 | Must pass | Passes |
| Sediment mg/l | FED-STD-791 M.3010 | 10 max | Passes |
| Ash mg/l | FED-STD-791 M.3010 | 1 max | Passes |
