Mobilgrease™ 33

Mobilgrease 33




 
Mobilgrease 33 is a high-performance lithium-complex grease designed for general-purpose aircraft use. Its consistency is between the NLGI grades 1 and 2.
Mobilgrease 33 utilizes a 100% polyalphaolefin base oil and premium additives which ensures outstanding lubrication performance over a wide temperature range and operating conditions.
 

To learn more, download the Mobilgrease 33 fact sheet >>

The lithium complex thickener system provides excellent structural stability and resistance to water wash-out. Polyalphaolefin base oil is used in Mobilgrease 33 because of its exceptional thermal/oxidative resistance potential, low volatility, and superb low-temperature capability, without the potential vulnerability of an ester base oil to degradation from reaction with water. The synthetic polyalphaolefin base oil offers excellent low-temperature mobility/pumpability and very low starting and running torque values. In addition, the state-of-the art additive system in Mobilgrease 33 provides superior rust and wear protection and load-carrying capacity compared to aviation greases that meet the minimum requirements of the MIL-PRF-23827 specification.

Mobilgrease 33, with its unique features, provides the following advantages and potential benefits:

FeaturesAdvantages and Potential Benefits
High viscosity index polyalphaolefin basestockVery wide operating temperature range - outstanding high and low temperature performance.
Excellent lubricant film protection at high temperatures
Good storage stabilityGrease structure integrity maintained - low oil separation
Exceptional resistance to thermal and oxidative degradationLong grease and lubricated part service life
Resistance to degradation by water (hydrolysis)No risk of corrosion induced by acidic base oil degradation products
Low volatilityLittle vulnerability to significant base oil loss by evaporation in service
Excellent protection against wear, corrosion, and rustingExcellent bearing and component protection
Extreme-pressure characteristicsPrevention of excessive wear, even under shock load
High resistance to water washoutExcellent grease performance in adverse weather and other water-exposure conditions

 

Applications

Mobilgrease 33 is a true multipurpose aviation grease intended for use in highly loaded anti-friction bearings, gears, and actuators as well as instruments, high speed bearings (though not recommended for wheel bearings), and general airframe lubrication, over operating temperatures from –100ºF to 250ºF (–73ºC to 121ºC). It can be used in all applications for which the aircraft manufacturer specifies U.S. Military Specification MIL-PRF-23827, Type I (Grease, Aircraft and Instrument, Gear and Actuator Screw, Grease thickened with metallic soap), Boeing BMS 3-33B (Grease, Aircraft, General Purpose), and Airbus AIMS09-06-002/SAE AMS3052 (Grease, General Purpose, Airframe, Low Temperature Range, Lithium Thickened).  Mobilgrease 33 is listed in the Qualified Products List of Airbus, Boeing, and the U.S. Military for these specifications. The NATO Code Number for Mobilgrease 33 is G-354.

Mobilgrease 33Is Approved AgainstMeets
Airbus AIMS09-06-002X 
Boeing BMS 3-33B Type 1X 
MIL-PRF-23827C, Amendment 2, Type IX 
NATO G-354X 
SAE AMS3052 X

 

 Test MethodsMIL-PRF-23827 Type IMobil-
grease 33 (1)
NLGI Grade  1 1/2
Thickener Type Metallic SoapLithium Complex
ColorVisual Blue Green
Structure/
Consistency
VisualSmooth, free from lumps and visual impuritiesPass
OdorOlfactoryNo rancid, perfume, or alcohol odor Pass 
Viscosity of Base Oil, cStASTM D 445  
at 40 ºC  12.5
at 100 ºC  3.2
Dropping Point, ºC (ºF)ASTM D 2265165 (329) min255 (491)
Low Temp. Torque at -73ºC (-100ºF), Nm DEF STAN 05-50 Part 62, ASTM D 1478  
Starting 1.00 max0.52 
Running, after 1 Hr 0.10 max0.06 
Low Temp. Torque with 10% water at -73ºC (-100ºF), NmDEF STAN 05-50 Part 62, ASTM D 1478   
Starting  0.67
Running, after 1 Hr   
Penetration at 25ºC (77ºF), mm/10DEF STAN 05-50 Part 63, ASTM D 217  
Unworked 200 min285
60 Strokes Worked 270-310292
100,000 Strokes WorkedFTM 313270-375330
Penetration, 100,000 Strokes Worked with 10% water, mm/10 DEF STAN 05-50 Part 63, ASTM D 217  330
Oil Separation, 30 Hrs at 100ºC, wt %ASTM D 61845 max 4
Evaporation Loss, 22 Hrs at 100ºC, wt %ASTM D 25952 max 1
Evaporation Loss, 500 Hrs at 121ºC, wt %ASTM D 2595  8.7
Copper Strip Corrosion, 24 Hrs at 100ºCASTM D 40481b max1b
AMS4640 Al/Ni Bronze Corrosion, 24 Hrs at 100ºCASTM D 4048  Pass
Four Ball Wear, scar dia., 1200rpm/40kg/1hr/75ºC, mmASTM D 2266  0.4
Load Wear Index, kgfASTM D 259630 min110
Weld Load, kgfASTM D 2596 700
Timken OK Load, lbfASTM D 2509 55
Rust Protection, 48 Hrs at 125ºF, ›1mm dia SpotsASTM D 1743 0 in 2 out of 3 bearings 0,0,0 
SKF EMCOR Rust, 3% NaCl, ratingASTM D 6138 0,0
Water Washout, 1 Hr at 38ºC (100 ºF), wt %ASTM D 126420 max3
Water Washout, 1 Hr at 79ºC (174 ºF), wt %ASTM D 1264  6
High Temperature Performance, Hrs at 121ºCASTM D 3336 1,000 min2,200+
Oxidation Stability, pressure drop in kPaASTM D 942  
100 Hrs at 99ºC 70 max11
500 Hrs at 99ºC 105 max25
Fretting Wear, mg lossASTM D 4170 0.6
Dynamic Bearing Life, No of cyclesBMS 3-33-8.2 Pass
Navy Gear Wear Test, mg loss/1000 cyclesFTM 335  
2.3 kg load 2.5 max1.1
4.5 kg load 3.5 max1.6
Dirt Count, Particles/mLFTM 3005  
25-74 Micron Size 1000 max0
75 Micron or Larger 00
Storage Stability, 6 months at 40ºC, Penetration, mm/10FTM 3467   
UnworkedASTM D 217200 min289
60x workedASTM D 217 288
60x worked, Difference from UnworkedASTM D 217 -1
Difference from OriginalASTM D 217±302
Elastomer Compatibility, 168 Hrs at 70ºC, % vol changeFTM 3603  
Nitrile (NBR-L, AMS3217/2)  +12.6
Thermoplastic Compatibility, 70 Hrs at 100ºC, % vol changeASTM D 4289  
Hytrel 6356 + 0.5% carbon black  3.4
Delrin 100 AF (ASTM D 4181)  +0.1
PTFE (Teflon) (AMS 3652)  +0.1
Nylatron GS  -0.5
(1) Values may vary within modest ranges  

 

 
Features & Benefits

The lithium complex thickener system provides excellent structural stability and resistance to water wash-out. Polyalphaolefin base oil is used in Mobilgrease 33 because of its exceptional thermal/oxidative resistance potential, low volatility, and superb low-temperature capability, without the potential vulnerability of an ester base oil to degradation from reaction with water. The synthetic polyalphaolefin base oil offers excellent low-temperature mobility/pumpability and very low starting and running torque values. In addition, the state-of-the art additive system in Mobilgrease 33 provides superior rust and wear protection and load-carrying capacity compared to aviation greases that meet the minimum requirements of the MIL-PRF-23827 specification.

Mobilgrease 33, with its unique features, provides the following advantages and potential benefits:

FeaturesAdvantages and Potential Benefits
High viscosity index polyalphaolefin basestockVery wide operating temperature range - outstanding high and low temperature performance.
Excellent lubricant film protection at high temperatures
Good storage stabilityGrease structure integrity maintained - low oil separation
Exceptional resistance to thermal and oxidative degradationLong grease and lubricated part service life
Resistance to degradation by water (hydrolysis)No risk of corrosion induced by acidic base oil degradation products
Low volatilityLittle vulnerability to significant base oil loss by evaporation in service
Excellent protection against wear, corrosion, and rustingExcellent bearing and component protection
Extreme-pressure characteristicsPrevention of excessive wear, even under shock load
High resistance to water washoutExcellent grease performance in adverse weather and other water-exposure conditions

 

Applications

Applications

Mobilgrease 33 is a true multipurpose aviation grease intended for use in highly loaded anti-friction bearings, gears, and actuators as well as instruments, high speed bearings (though not recommended for wheel bearings), and general airframe lubrication, over operating temperatures from –100ºF to 250ºF (–73ºC to 121ºC). It can be used in all applications for which the aircraft manufacturer specifies U.S. Military Specification MIL-PRF-23827, Type I (Grease, Aircraft and Instrument, Gear and Actuator Screw, Grease thickened with metallic soap), Boeing BMS 3-33B (Grease, Aircraft, General Purpose), and Airbus AIMS09-06-002/SAE AMS3052 (Grease, General Purpose, Airframe, Low Temperature Range, Lithium Thickened).  Mobilgrease 33 is listed in the Qualified Products List of Airbus, Boeing, and the U.S. Military for these specifications. The NATO Code Number for Mobilgrease 33 is G-354.

Specs
Mobilgrease 33Is Approved AgainstMeets
Airbus AIMS09-06-002X 
Boeing BMS 3-33B Type 1X 
MIL-PRF-23827C, Amendment 2, Type IX 
NATO G-354X 
SAE AMS3052 X

 

Tech Details
 Test MethodsMIL-PRF-23827 Type IMobil-
grease 33 (1)
NLGI Grade  1 1/2
Thickener Type Metallic SoapLithium Complex
ColorVisual Blue Green
Structure/
Consistency
VisualSmooth, free from lumps and visual impuritiesPass
OdorOlfactoryNo rancid, perfume, or alcohol odor Pass 
Viscosity of Base Oil, cStASTM D 445  
at 40 ºC  12.5
at 100 ºC  3.2
Dropping Point, ºC (ºF)ASTM D 2265165 (329) min255 (491)
Low Temp. Torque at -73ºC (-100ºF), Nm DEF STAN 05-50 Part 62, ASTM D 1478  
Starting 1.00 max0.52 
Running, after 1 Hr 0.10 max0.06 
Low Temp. Torque with 10% water at -73ºC (-100ºF), NmDEF STAN 05-50 Part 62, ASTM D 1478   
Starting  0.67
Running, after 1 Hr   
Penetration at 25ºC (77ºF), mm/10DEF STAN 05-50 Part 63, ASTM D 217  
Unworked 200 min285
60 Strokes Worked 270-310292
100,000 Strokes WorkedFTM 313270-375330
Penetration, 100,000 Strokes Worked with 10% water, mm/10 DEF STAN 05-50 Part 63, ASTM D 217  330
Oil Separation, 30 Hrs at 100ºC, wt %ASTM D 61845 max 4
Evaporation Loss, 22 Hrs at 100ºC, wt %ASTM D 25952 max 1
Evaporation Loss, 500 Hrs at 121ºC, wt %ASTM D 2595  8.7
Copper Strip Corrosion, 24 Hrs at 100ºCASTM D 40481b max1b
AMS4640 Al/Ni Bronze Corrosion, 24 Hrs at 100ºCASTM D 4048  Pass
Four Ball Wear, scar dia., 1200rpm/40kg/1hr/75ºC, mmASTM D 2266  0.4
Load Wear Index, kgfASTM D 259630 min110
Weld Load, kgfASTM D 2596 700
Timken OK Load, lbfASTM D 2509 55
Rust Protection, 48 Hrs at 125ºF, ›1mm dia SpotsASTM D 1743 0 in 2 out of 3 bearings 0,0,0 
SKF EMCOR Rust, 3% NaCl, ratingASTM D 6138 0,0
Water Washout, 1 Hr at 38ºC (100 ºF), wt %ASTM D 126420 max3
Water Washout, 1 Hr at 79ºC (174 ºF), wt %ASTM D 1264  6
High Temperature Performance, Hrs at 121ºCASTM D 3336 1,000 min2,200+
Oxidation Stability, pressure drop in kPaASTM D 942  
100 Hrs at 99ºC 70 max11
500 Hrs at 99ºC 105 max25
Fretting Wear, mg lossASTM D 4170 0.6
Dynamic Bearing Life, No of cyclesBMS 3-33-8.2 Pass
Navy Gear Wear Test, mg loss/1000 cyclesFTM 335  
2.3 kg load 2.5 max1.1
4.5 kg load 3.5 max1.6
Dirt Count, Particles/mLFTM 3005  
25-74 Micron Size 1000 max0
75 Micron or Larger 00
Storage Stability, 6 months at 40ºC, Penetration, mm/10FTM 3467   
UnworkedASTM D 217200 min289
60x workedASTM D 217 288
60x worked, Difference from UnworkedASTM D 217 -1
Difference from OriginalASTM D 217±302
Elastomer Compatibility, 168 Hrs at 70ºC, % vol changeFTM 3603  
Nitrile (NBR-L, AMS3217/2)  +12.6
Thermoplastic Compatibility, 70 Hrs at 100ºC, % vol changeASTM D 4289  
Hytrel 6356 + 0.5% carbon black  3.4
Delrin 100 AF (ASTM D 4181)  +0.1
PTFE (Teflon) (AMS 3652)  +0.1
Nylatron GS  -0.5
(1) Values may vary within modest ranges  

 

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