Lubricant and Hydraulic Fluid Information.

NAVAIR 17-15-50.4

TM 38-301-4

T.O. 33-1-37-4

CGTO 33-1-37-4

2-3. Lubricant and Hydraulic Fluid Information.

a. Specifications. Military specifications for lubricants and hydraulic fluids are frequently published in a

format which includes sections describing the intended use of the oil/fluid, referenced documents, lubricant/fluid

property requirements, level of performance, quality assurance provisions, test procedures for determination of

properties, packaging and marking instructions, and qualification procedures. A specific military agency is

responsible for the qualification of oils/fluids to each specification. The agency determines, from in-house or

commercial laboratory evaluation data that products submitted for qualification meet all specification

requirements. Periodically, an updated submitted for qualification meet all specification requirements. Periodically,

an updated qualified products lists (QUPL) is published for each specification giving the government designation

(if any) for the lubricant, the manufacturer's designation for the lubricant/fluid, a test or qualification reference

number/fluid, and the manufacturer's name and address.

b. Military and NATO Symbols. Lubricating engine and gear oils and hydraulic fluids are generally

identified by military symbols and, in some instances, NATO Code Number designations. To provide a ready

reference for specification products, table 2-1 lists military lubricant and hydraulic fluid specifications with their

respective grade and military and NATO designations.

Within the confines of this discussion, a lubricant serves the following functions.

(1) Provides a film to reduce friction between rolling and sliding hardware components, i.e., roller and

ball bearings and races, sleeve bearings and shaft surfaces, piston rings and cylinder liners, etc. Adequate

lubricant film strength under extreme pressures and temperatures assures minimum metal-to-metal scuffing,

scoring, and reduced overall wear.

(2)

Provides a medium to transfer heat caused by friction from critical working surfaces.

(3)

Acts as a flushing liquid to carry away wear particles and other foreign material.

(4)

Contains additives which:

(a)

Suspend combustion blow-by products and debris in the oil.

(b)

Provide a sealing medium in piston engines.

(c)

Maintain the cleanliness of critical component surfaces.

(d)

Chemically react with power-system produced contaminates to neutralize their adverse

effects.

Additives.

(1) Additives are normally classified as detergents, dispresants, oxidation inhibitors, corrosion

inhibitors, anti-wear agents, pour point depressants, or anti-foam agents.

2-3