Mobil 254 Turbine Oil, MIL-PRF-23699-HTS

Key Features

• 5 cSt synthetic aircraft turbine oil
• MIL-PRF-23699F HTS high thermal stability classification
• SAE AS5780 HPC high performance capability classification
• Excellent thermal and oxidation stability
• High resistance to carbon coking and deposit formation
• Excellent wear and corrosion protection
• Low evaporative loss helps reduce oil consumption
• Excellent resistance to foaming
• Good low-temperature fluidity
• Effective operating range from approximately -40°F to 450°F
• Designed for severe operating conditions in aircraft-type gas turbines

Aircraft and Turbine Applications

Mobil Jet Oil 254 is recommended for aircraft gas turbine engines where a MIL-PRF-23699 HTS / SAE AS5780 HPC lubricant is specified.

• Turbojet engines
• Turbofan engines
• Turboprop engines
• Turboshaft and helicopter engines
• Aircraft auxiliary power units and accessories
• Constant-speed drives
• Integrated-drive generators
• Aircraft-type gas turbines used in industrial or marine applications

Important: Specific engine or component approval must be verified against the applicable aircraft, engine, accessory, or component manufacturer's technical documentation. Do not select or substitute turbine oil solely on the basis of viscosity or specification classification.

Specifications and Approvals

Mobil Jet Oil 254 has builder approvals covering a wide range of aircraft engines and accessories. Specific engine and equipment applicability should always be verified with the applicable manufacturer's documentation.

Typical Physical Properties

The following values are typical properties published by ExxonMobil for Mobil Jet Oil 254. They are provided for technical reference and are not guaranteed shipment specifications.

High-Temperature Performance

Mobil Jet Oil 254 was developed specifically for the demanding thermal conditions encountered in modern aircraft gas turbine engines. ExxonMobil reports excellent bulk oil stability at temperatures up to 232°C / 450°F for extended periods, along with resistance to oxidation, coking, and deposit formation.

Compared with typical Standard Type II turbine lubricants, Mobil Jet Oil 254 is designed to provide improved high-temperature bulk-oil stability and deposit control. This helps protect bearings, gears, and other critical components operating under severe thermal conditions.

Low-Temperature Performance

Mobil Jet Oil 254 provides good low-temperature fluidity, with ExxonMobil identifying effective starting and lubrication performance at temperatures as low as -40°C / -40°F. The published pour point is approximately -62°C.

Packaging and Shelf Life

Important shelf-life note: ExxonMobil states that once a container is opened, the product should be used as soon as possible to avoid contamination and degradation. The stated shelf life no longer applies once the container has been opened.

Mobil Jet Oil 254 vs. Other MIL-PRF-23699 Turbine Oils

Mobil Jet Oil 254 and Eastman Turbo Oil 2197 are both 5 cSt synthetic turbine oils in the HTS/HPC class. Eastman Turbo Oil 2380 is a 5 cSt STD/SPC product. The correct lubricant should always be selected according to the applicable aircraft, engine, accessory, or component documentation.

Frequently Asked Questions

What is Mobil Jet Oil 254?

Mobil Jet Oil 254 is a 5 cSt synthetic aircraft gas turbine lubricant designed for severe operating conditions. It is a high thermal stability (HTS) turbine oil qualified to MIL-PRF-23699F HTS and SAE AS5780 HPC.

What specification does Mobil Jet Oil 254 meet?

Mobil Jet Oil 254 is qualified to MIL-PRF-23699F HTS and SAE AS5780 HPC.

What viscosity is Mobil Jet Oil 254?

Mobil Jet Oil 254 is a 5 cSt class synthetic aircraft turbine oil. Its published kinematic viscosity is 5.3 mm²/s at 100°C.

What is the difference between Mobil Jet Oil 254 and Mobil Jet Oil II?

Mobil Jet Oil 254 is the higher-performance HTS/HPC product, while Mobil Jet Oil II is a Standard Type II / STD-class turbine lubricant. The correct product depends on the requirements of the specific aircraft engine or component.

Is Mobil Jet Oil 254 a high-temperature turbine oil?

Yes. High thermal stability is one of the defining characteristics of Mobil Jet Oil 254. ExxonMobil reports excellent bulk oil stability up to approximately 232°C / 450°F for extended periods.

What aircraft engines use Mobil Jet Oil 254?

ExxonMobil lists builder approvals covering engines from manufacturers including CFM International, GE, International Aero Engines, Pratt & Whitney, Pratt & Whitney Canada, Rolls-Royce, and Honeywell. Specific engine or equipment applicability must be verified with the manufacturer.

What is the shelf life of Mobil Jet Oil 254?

ExxonMobil currently recommends 10 years for quart packages, 5 years for pails and drums, and 2 years for totes. Once a container is opened, ExxonMobil recommends using the product as soon as possible because the stated shelf life no longer applies.