TYPICAL PROPERTIES:

PROPERTY Viscosity, cSt @210°F @100°F @-40°F Flash Point, °F (C.O.C.) Fire Point, °F Pour Point, °F Neutralization No. Synthetic Rubber Swell “H” (72 hrs/158°F),% Swell “F” (72 hrs/400 °F), % Thermal Stability (96 hrs/525 °F) Viscosity; @ 100 °F, % Change Acid Number Change, mg KOH/g Metal Weight Change, mg/cm2 Oxidation and Corrosion Stability (72 hrs/400 °F) Corrosion Steel, wt. change, mg/cm2 Silver, wt. change, mg/cm2 Aluminum, wt. change, mg/cm2 Magnesium, wt. change, mg/cm2 Copper, wt. change, mg/cm2 Oxidation Viscosity Change @ 100°F, % Total Acid Number Change Contamination, mg/100 ml Load Carrying Capacity, Ryder Gear @ 165° Scuff Rating, lb/in2 Relative Rating, % Sediment, 1.2 micron filter, mg/L Foaming, ml initial/ml final Seq I @ 77°F Seq II @ 200°F Seq III @ 77°F Specific Heat, Cp @ 37.8 °C @ 260°C Dynamic Rust Test, synthetic sea water Degree of rusting, 60°C, 24 hrs API Gravity

SPECIFICATION 5.0-5.5 25 min. 13,000 max. 475 min. -65 max. 0.5 max 5.0-25.0 5.0-25.0 5.0 max. 6.0 max. + 4.0 max.   + 0.2max. + 0.2 max. + 0.2 max. + 0.2 max. + 0.2 max. -5 to +25 3.0 max. 50.0 max. Typical Typical 10 max. 25/0 25/0 25/0 Typical Typical None

TYPICAL 5.40 29.5 10,300 508 555 -75 0.3 12.5 14.7 1.3 1.75 0.40 0.02 0.02 0.01 0.03 0.05 12.5 0.6 0.9 3835 155 2.0 nil nil nil 0.466 0.618 PASS 10.89

*Qualification test not normally performed for routine quality conformance.

APPLICATIONS:
ROYCO 555 was specifically developed for use in high performance gas turbine engines developed during the mid 1960’s for the SST and Concorde. These advanced engines required a lubricant having good high temperature stability as well as extreme pressure load carrying capability. ROYCO 555 was developed for the demands of increasingly higher power output engines that subsequently develop higher operating temperatures
and loads. It was also designed to give improved performance in current engines.
ROYCO 555 was also formulated to meet the requirements of helicopter gearbox and transmission systems. A high load carrying oil such as ROYCO 555 is necessary to meet the load requirements and reliability demands
of those systems. More recently with the need to transmit more power and higher loads through helicopter gearbox and transmission systems, extensive evaluation by helicopter airframe manufacturers has demonstrated this improved load carrying ability which has resulted in improved reliability - particularly by increased time between overhaul (TBO.) This oil should only be used in applications where synthetic oils have been
specified or in systems expressly designed for synthetic lubricants.
NOTE: ROYCO 555 should not be used with silicone-based elastomers.

PACKAGING:
ROYCO 555 is available in 55 gallon drums, 5 gallon pails, and 1 quart cans packed twenty-four to a carton.

SPECIFICATIONS:
ROYCO 555 meets the requirements of and is qualified under U.S. Military specification: DoD-PRF-85734 as well as meeting the requirements of:
▪ U.K. DERD.2497 ▪ XAS-2354 ▪ British DEF STAN 91-100 ▪ NATO Code O-160
▪ UK Joint Service Designation OX-26 ROYCO 555 is approved commercially for use in aircraft transmissions, gearboxes, and gas turbine engines
manufactured by Pratt & Whitney (521C Type II), Pratt & Whitney Canada, IAE, CFM International, General Electric (D-50 TF 1), RR Allison (EMS-53 (Obsolete)) , Rolls Royce, Garrett, Motorlet, and Turbomeca, as well as Garrett and Sunstrand accessories. A detailed application list is available upon request. ROYCO 555 is also approved for use in Eurocopter/Aerospatiale, Boeing Vertol, Bell Helicopter Textron, Agusta,
Hughes/McDonnell Douglas, MBB, Sikorsky, and Westland helicopter transmissions.