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Royco 555 Synthetic Turbine Engine Oil (OX-26) (O-160) 1USQ Can *DOD-PRF-85734

Royco 555 Synthetic Turbine Engine Oil (OX-26) (O-160) 1USQ Can *DOD-PRF-85734
ROYCO 555 is an advanced 5 centistoke synthetic lubricating oil for gas turbine engines and helicopter transmissions. The product is a blend of hindered polyol esters and a finely balanced modern technology additive package resulting in enhanced load carrying performance, antiwear, corrosion protection, and excellent thermal - oxidative stability.
£25.02 excl VAT
£30.02 inc VAT
No stock - lead time 59 days
Please order in multiples of 24
Commodity Code: 34031980
Bulk discounts
£25.02 + VAT
£24.36 + VAT
£23.71 + VAT


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 temperaturestability 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.


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.

Orders over £50 placed online will now qualify for FREE UK Mainland delivery*

Orders under £50 placed online for UK Mainland delivery is £6.95*

Orders requiring Pre 10.00am Next Day delivery has also been lowered from £35.00 to £19.50** 

International delivery (door to door delivery) is available for selected countries worldwide. Shipping will be automatically calculated based on the weight, location and hazardous nature of the goods. Customers can also choose ex works to arrange their own collection.
Please refer to our delivery page for more information.

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Sil-Mid Limited DO NOT GUARANTEE that the information on this page is the most up to date information available from the manufacturer, there are times when updated information is released and we are not made aware immediately.