|  | Exxon Mobil Mobilgrease 28 Red Synthetic Aviation GreaseProper lubrication is the key tp keeping your aircraft running smoothly and prolonging the life of your most sensitive components. A reliable aviation grease protects sensitive parts from excessive wear due to friction, reducing maintenance demands and extending the life of vital systems. When it comes to aviation applications, nothing cuts back on friction as well as MobilGrease 28 from SkyGeek. MobileGrease 28 is a specially formulated aviation lubricant, made from synthetic polyalphaolefin compounds (PAO) and a non-soap, organo-clay thickener. It's red in color so it's easy to spot as it protects, lubricates and enhances your aircraft's most important engine components. Mobil 28 Grease is an anti-wear red grease that works overtime to reduce frictional drag, increasing the lifespan of your aircraft's bearings.
In addition to protecting against the ravages of friction, the PAO and clay thickener provides low-traction, water resistance and a low running torque. It reduces abrasions that can cause high temperatures, protecting your aircraft's engine from overheating, which can cause premature wear and tear. Mobil 28 Grease is an industry leader and is a top choice of pilots, aircraft mechanics and other professionals. It has been the leading grease in the aviation industry for over three decades and can still be found in hangars and on workbenches throughout the world. If you're looking for MobilGrease 28 aviation lubricant, buy it here at SkyGeek and enjoy our low everyday prices and excellent customer service. We carry Mobil 28 red grease for sale in various sizes and container styles to suit your needs. Buy a little for a single hobby plane or pick up a large drum of the high-performance grease for use on your entire fleet. See detailed information on this page and the MSDS regarding safe handling and usage. For questions or for help ordering, please do not hesitate to contact us.
- Conforms to U.S. Military Specifications, including MIL-G-81322E
- Can be used on rotor bearings, screw jacks, landing wheel assemblies and oscillating bearings
- Works well in the components of servo devices, actuators and control systems
- Available in various container sizes
Approvals/References/Specification
- NATO Specification: G-3952
- US Military Specification: NLGI Grade 1
- US Military Specification: DOD-G-24508A, Amendment 4
- US Military Specification: MIL-G-81322 Grade B
- US Military Specification: MIL-PRF-81322G
Applications Mobilgrease 28 is designed for the lubrication of plain and rolling bearings at low to high speeds, and splines, screws, worm gears, and other mechanisms where high friction reduction, low wear, and low lubricant friction losses are required. The recommended operating temperature range is -55°C to 180°C with appropriate relubrication intervals.
Mobilgrease 28 meets the quality level of military specifications MIL-G-81322 for wide temperature range aviation service and is approved under DOD-G-24508A for shipboard service. Specific military and civil aviation applications include: Landing wheel assemblies
Control systems, screwjacks, servo devices, actuators, sealed-bearing motors and oscillating bearings
Helicopter rotor bearings on aircraft and on naval shipboard auxiliary machinery
It also can be used where superseded specifications MIL-G-81322 (WP), MIL-G-7711A, MIL-G-3545B, and MIL-G-25760A may be called for
Mobilgrease 28 also is recommended for industrial lubrication, including sealed or repackable ball and roller bearings wherever extreme temperature conditions, high speeds, or water washing resistance are factors. Typical industrial applications include:
Conveyor bearings
Small alternator bearings operating at temperatures near 177°C
High-speed miniature ball bearings, and bearing situations where oscillatory motion, vibration, and fretting create problemsFeatures Mobilgrease 28 is one of many Mobil branded PAO-based products recognized around the world for innovation and
outstanding performance. Synthetic products like Mobilgrease 28 represent ExxonMobil's, continuing commitment to
using advanced technology to provide outstanding products. Close contacts between ExxonMobil scientists and
application specialists and key equipment builders ensure that our products meet the needs of the latest aviation
equipment designs. Good resistance to high temperature stresses and excellent starting and low torque at low-temperature are two of
the most important requirements of aviation greases.To meet this combination of needs our product formulation
scientists chose proprietary synthetic base oils for Mobilgrease 28 because of their exeptional thermal/oxidative
resistance potential, and superb low-temperature capability. Our formulators chose specific thickener chemistry and
a prorietary additive combination which would maximize the benefits of the synthetic base oils. Mobilgrease 28 meets the requirements of key military and commercial aviation specifications and has built up an
excellent reputation for performance and reliability among users around the world. Mobilgrease 28 provides the
following advantages and potential benefits:
Features | Advantages and Potential Benifits |
High viscosity index base stock with no wax content | Very wide operating temperature range -
outstanding high and low temperature performance |
| Excellent film protection at high temperatures |
| Minimum resistance to start-up at extremely low temperatures |
Low traction base oil | Low sliding friction and reduced heat build-up |
| Potential for energy savings |
Excellent protection against fretting wear and corrosion | Superb bearing protection and extended bearing life and
reduced bearing replacement costs |
Extreme-pressure characteristics | Avoids excessive wear, even under shock load |
High thermal/oxidative stability | Extended relubrication intervals |
High resistance to water washout | Maintains excellent grease performance in adverse weather
and other water-exposure conditions |
Specifications

| 
Test Methods
| 
Mobilgrease 28 (1)
| 
MIL-PRF-81322 Limits
|
NLGI Grade | | 1 1/2 | |
Thickener Type | | Clay (non-soap) | |
Color | Visual | Dark Red | |
Structure | Visual | Smooth, buttery | |
Dropping Point, ºC (ºF) | ASTM D 2265 | 315 (599) | 232 (450) min |
Viscosity of Base Oil, cSt | ASTM D 445 | | |
at 40ºC | | 29.3 | |
at 100ºC | | 5.6 | |
Low Temp. Torque at -54ºC (-65ºF), Nm (g-cm) | ASTM D 1478 | | |
Starting | | 0.83 (8500) | 0.98 (10,000) max |
Running, after 1 Hr | | 0.08 (800) | 0.098 (1,000) max |
Penetration @ 25ºC (77ºF), 60 Stoke Worked, mm/10 | ASTM D 217 | 295 | 265-320 |
Extended Worked Penetration Stability, 100,000 Strokes, mm/10 | FTM 313 | 302 | 350 max |
Oil Separation, 30 Hrs at 177ºC, wt % | ASTM D 6184 | 2.5 | 2.0 - 8.0 |
Evaporation Loss, 22 Hrs at 177ºC, wt % | ASTM D 2595 | 6 | 10 max |
Copper Strip Corrosion, 24 Hrs at 100ºC | ASTM D 4048 | Pass | 1b max |
Four-Ball Wear, Scar dia, mm | ASTM D 2266 | 0.5 | 0.8 max |
Load Wear Index, kgf | ASTM D 2596 | 42 | 30 min |
Rust Protection, 48 Hrs at 125ºF, › 1mm dia Corrosion Spots | ASTM D 1743 | Pass | 0 |
Water Washout, 1 Hr at 41ºC, wt % | ASTM D 1264 | 1 | 20 max |
High Temperature Performance, Hrs at 177ºC | ASTM D 3336 | Pass | 400 min |
Oxidation Stability, pressure drop in kPa | ASTM D 942 | | |
100 Hrs at 99ºC | | Pass | 83 max |
500 Hrs at 99ºC | | Pass | 172 max |
Storage Stability, 6 months at 38ºC | FTM 3467 | Pass | Pass |
Dirt Count, Particles/mL | FTM 3005 | | |
25-74 Micron | | Pass | 1000 max |
75 Micron or Larger | | 0 | 0 |
Oscillation Friction and Wear, Scar Dia, 35,000 cycles, 90º Angle, Aluminum Bronze Block, mm | Modified ASTM D 3704 | Pass | 6.35 max |
Rubber Swell, L Type Synthetic, 1 week at 70ºC (158ºF), vol % | FTM 3603 | 6 | 10 max |
(1) Values may vary within modest ranges | | | |
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