These descriptions are general in nature and may not be absolutely
Acid Number or Total Acid Number – is a measurement of the acidic properties
of an oil. The acid number of an oil increases during the service life of the oil due
to acid build-up in the oil.
AGMA – American Gear Manufacturers Association
Anti-wear Additive – is an additive used to reduce the amount of wear between
two sliding surfaces by reacting with the metal surface to form a film. Zinc (dialkyl
dithiophosphate) is the most common type used.
API – American Petroleum Institute
Ash or Sulphated Ash – is an measurement of the residue left behind after the
combustion of an oil. Metallic (calcium and magnesium) detergents and (zinc)
antiwear additives contribute to the ash content of an oil.
ASTM – American Society for Testing and Materials. This group establishes many
of the test methods used by laboratories to evaluate oils and greases.
Autoignition Temperature (AIT) – is the temperature to which an oil can be
heated before it will spontaneously ignite, even without a source of ignition. The
AIT will occur at a higher temperature than the flash point or fire point of an oil.
Base Number or Total Base Number – is a measure of the basic or alkaline
properties of an oil. The base number of an oil decreases during the service life
of an oil due to the consumption of some of the additives in the oil.
Base Oil or Base Stock – is the lubricating oil portion of a lubricating oil or
grease. It may be mineral (refined from crude oil) or synthetic (manufactured,
Brookfield Viscosity – a low temperature viscosity used to evaluate hydraulic oils
and gear oils.
CCS – Cold Cranking Simulator, is a low temperature viscosity used to evaluate the
start-up performance of motor oils.
Centistoke – (cSt) A common unit of kinematic viscosity.
Equal in value to a mm2/s.
Centipoise – (cP) A common unit of absolute or dynamic viscosity. Results from
Brookfield, Cold Cranking Simulator and Mini Rotary viscometers provide results in
centipoise. Equal in value to a milli Pascal second (mPa.s).
CGSB – Canadian General Standards Board, establish standard laboratory test
methods for Canada.
Channel Point – is the lowest temperature at which an oil will slump back into
a channel cut through the oil. It is used to simulate gear teeth moving through
Compounded Oil – is a lubricating oil containing fatty (natural or synthetic)
Demulsibility – is the ability of an oil to allow water to separate (drop-out).
Dropping Point – is the highest temperature to which a grease can be heat before
a drop of oil separates (and drops) from the grease (under prescribed conditions).
EP – Extreme Pressure – is a term used to describe an oil or grease which
contains an additive used to protect metal surfaces from heavy loading and shock
loading by reacting with the metal surface to reduce the potential damage.
Common in gear oils and multipurpose greases.
Four (4) Ball Test – 4 Ball Wear test measures the wear protection provided by a
lubricant by measuring a scar diameter on four steel balls. A smaller scar diameter
indicates better wear protection.
4 Ball EP test measures the extreme pressure load carrying capacity of a lubricant.
A higher load causing the welding of the balls (Weld Load) and a higher calculated
Load Wear Index (LWI), determined prior to welding, indicate better EP protection.
Flash Point – is the lowest temperature at which an oil creates enough flammable
vapour to ignite in the presence of a spark, but not sustain a flame.
COC – Cleveland Open Cup Method, used for lubricating oils.
PMCC – Pensky-Martens Closed Cup Method, used for fuel oils and lubricants
containing lighter solvents.
TAGCC – Tag Closed Cup Method, used for solvents.
ISO – International Standards Organization
Lubricant – an oil or grease or solid used to reduce friction between two moving
surfaces in contact.
Mineral Oil – is base oil (or base stock) derived directly from crude oil at a refinery.
The crude oil is cleaned-up by various solvent extraction, hydrofinishing, hydrotreating
and dewaxing processes and separated into different viscosity grades.
MRV – Mini Rotary Viscometer, is a low temperature viscosity used to measure the
ability of an oil to be pumped within an automotive engine. It is used to prevent oil
starvation during engine start-up.
Neutralization Number – is another term used to refer to either the acid number
or base number of an oil.
NLGI – National Lubricating Grease Institute.
Penetration – is used to determine the NLGI grade number (the hardness or
stiffness) of a grease e.g. a #2 grade grease.
R&O – is an oil containing primarily just a rust and oxidation inhibiting additive
package. It may contain an antifoam additive but will not contain an antiwear or
SAE – Society of Automotive Engineers.
Solvent Extraction – a refining process for mineral base oils that is used to
remove undesirable chemical components.
STLE – Society of Tribologists and Lubrication Engineers.
Sulphated Ash – See Ash.
Synthetic – man-made, structurally altered (not naturally occurring) base oil.
Various chemical types exist with different properties.
Synthetic Blend – is a formulated lubricating oil containing both mineral oil base
stock and synthetic oil base stock. The proportion of mineral oil to synthetic oil
can vary widely.
Timken OK Load – is a measure of the extreme pressure (EP) properties of an oil
or grease. The “OK Load” is the heaviest load that a film of lubricant can support
without scoring under the test conditions. Test results can vary significantly.
Total Acid Number (TAN) – See Acid Number
Total Base Number (TBN) – See Base Number
Kinematic Viscosity Comparison Chart
210°F limits converted to 40°C on basis of 95 VI oils
NLGI Grease Grade Definitions
Penetration Range Comments
# 000 475 to 445 semi-fluid, used in some gearboxes
# 00 430 to 400 used in centralized systems
# 0 385 to 355 used in centralized systems
# 1 340 to 310 grease gun & centralized systems
# 2 295 to 265 most common grade, grease gun
# 3 250 to 220 grease gun, higher speed bearings
# 4 205 to 175 not common
# 5 160 to 130 not common
# 6 115 to 85 hard, block grease, not common
SAE Engine Oil Viscosity Grade Definitions
Viscosity CCS MRV Min. Max. High
Grade Cranking Pumping Kinematic Kinematic Shear (cP)
(cP) Max @ °C (cP) Max @ °C Viscosity Viscosity @ 150°C
@ 100°C @ 100°C
0W 6,250 @ -35° 60,000 @ -40° 3.8 — —-
5W 6,600 @ -30° 60,000 @ -35° 3.8 — —-
10W 7,000 @ -25° 60,000 @ -30° 4.1 — —-
15W 7,000 @ -20° 60,000 @ -25° 5.6 — —-
20W 9,500 @ -15° 60,000 @ -20° 5.6 — —-
25W 13,000 @ -10° 60,000 @ -15° 9.3 — —-
20 — — 5.6 < 9.3 2.6
30 — — 9.3 < 12.5 2.9
40 — — 12.5 < 16.3 2.9 (0W,
40 — — 12.5 < 16.3 3.7 (15W,
50 — — 16.3 < 21.9 3.7
60 — — 21.9 < 26.1 3.7
All values are critical specifications as defined by ASTM D 3244
SAE J-300 (Dec 99 Revision)
SAE Gear Oil Viscosity Grade Definitions
PROPERTY 75W 80W 85W 90 140 250
100°C Min. 4.1 7 11 13.5 24.0 41
Max. 24.5 41.0
Max. Temp (°C)
for 150,000 cP
Brookfield Visc. -40° -26° -12° — — —
ISO Viscosity Grade Definitions
ISO Grade Grade Minimum Grade Maximum
10 9 11
15 13.5 16.5
22 19.8 24.2
32 28.8 35.2
46 41.4 50.6
68 61.2 74.8
100 90 110
150 135 165
220 198 242
320 288 352
460 414 506
680 612 748
1000 900 1100
1 litre = 0.220 Imp gallons = 0.264 US gallons = 0.0010 cubic meters
1 Imp gallon = 4.546 litres = 1.20 US gallons = 0.00455 cubic meters
1 US gallon = 3.785 litres = 0.8327 Imp gal. = 0.003785 cubic meters
1 cubic meter = 1000 litres
1 cubic inch = 16.4 cc or ml 1 cc = 0.0610 cubic inches
1 Bbl = 159 litres = 35 Imp Gallons
1 inch = 25.4 mm
1 foot = 0.3048 meters
1 yard = 0.0144 meters
1 mile = 1.6093 km
1 ounce = 28.35 grams
1 pound = 0.454 kilograms 1 kilogram = 2.205 pounds
°F = (°C x 9/5) + 32
°C = (°F – 32) x 5/9
100 kPa = 14.504 PSI = 1 bar
1 PSI = 6.895 kPa
1 Watt = 3.41 BTU’s / hr