Compatibility of greases explained

The grease compatibility chart is found everywhere in grease and lubrication circles. But behind its common "wisdom" is many misconceptions regarding grease compatibility. Just because the chart says lithium complex and Calcium Sulphonate are compatible, isn't really representative of performance in a bearing or gearbox. In fact, the ASTM standard that most labs test to defines a secondary set of (much more useful tests) that no one is using!
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Hi I’m Rafe Britton, the Lubrication Expert. I’m known within the industry for my TH-cam channel and podcast, and I work with mid-size industrials improve their equipment uptime while reducing the cost of their lubrication program. I’m a mechanical engineer with 13 years of experience on both sides of the industry; both as an operator, and lubricant supplier. I hold a Bachelor of Aerospace Engineering and a Bachelor of Physics from UNSW.
Lubrication Expert is purposefully brand independent and sells no lubricant, filter, sensor or hardware. I’ve helped dozens of industrial clients upskill their workforce, reduce waste, improve reliability and take great strides toward their corporate sustainability goals. I serve on the Australian Lubricant Association technical committee to push the lubrication industry forward.
Industry doesn’t understand lubrication, and few people are left to teach them. This results in incorrect use of lubricants, contamination & machine failure, leaving reliability engineers frustrated with the state of their lubrication program. The ultimate consequence is more machine interventions, more waste, and more equipment downtime
What I offer is knowledge, and only knowledge. My clients gain access to my learnings both as an operator and industry insider - this includes the technical aspects of lubricant chemistry, degradation and contamination control, but also the commercial considerations so that you can better leverage your supplier relationships.
The result? A world-class lubrication program that optimizes for reliability, reduces waste and improves sustainability outcomes.

[@kthnos]

this channel is gold !

[@LubricationExplained]

Thanks!!

[@jankowalskijfk]

Great materiał, thank You!

[@sunrevolver]

This is gold

[@ID10Tpig]

So what about mixing two NLGI #2 lithium complex greases. One is gray with a small percentage of moly and the other red with no moly.

[@sunrevolver]

the only way to know is to try and see the results. My guess would be it won't be good because the dilution of the Moly. I believe the Moly is there for a reason.

[@mikeadler434]

👍👍

[@tthams73]

Li & Ca - Sulph are often used in combination in a single grease complex. There is no compatibility issues.
Base oils are all compatible and do NOT interact.
Grease compatibility is a standard test performed by manufacturers and required for certification.

[@LubricationExplained]

This is very misleading. Base oils have known incompatibility issues - the most common is certain PAGs and PAOs which tend to form grease-like deposits when mixed.
Grease compatibility may be performed during formulation, but it’s impossible to test against every thickener, additive, and base oil combination. This is why end users must perform their own testing, especially when changing grease in equipment deemed critical.

[@bmfilmnut]

For the typical person who watches this video this is not helpful. Are you actually suggesting that some guy who has to mix grease types should contact testing lab to run tests on the two greased he's about to mix when he has to mix greases for some reason? Come on! This reminds me of Peter Lynch's advice to investors that they should meet with the CEO of any company they are interested in buying their stock. Your advice has no practical or realistic value to regular folks.

[@sunrevolver]

For the general rules, don't mix different type of lubricants.
mixing lubricants is mainly for people who have access to do testing and really really understand what they are doing.

[@jankowalskijfk]

Great materiał, thank You!

[@LubricationExplained]

Thanks so much! Hope you found it helpful.