[beertracker]

If a grease is advertised as NLGI number 2 is it a Extreme Pressure grease?

[XLR8STEVE]

i used Lucas Extra Heavy Duty Grease on my trailer bearings this year. it is that grade but also in the tech sheet says extreme pressure. great stuff.

https://lucasoil.com/products/grease...vy-duty-grease

[Schurkey]

Originally Posted by beertracker

If a grease is advertised as NLGI number 2 is it a Extreme Pressure grease?

NLGI #2 is "normal thickness" grease.

Grease is rated from #6 (hard-stiff) to #000 which is runny-liquid. The NLGI number is the equivalent to saying 10-weight motor oil, or 50-weight motor oil.

Practically all automotive grease--wheel bearings, ball joints, etc, is going to be NLGI #2.
Rear axle fluid is typically sold as "oil" or "lube", not "grease". I have some "Engine Assembly Grease" that looks like wheel bearing grease, only thinner--it's NLGI #0.5

The thickness/stiffness has NOTHING to do with whether it's suitable for "Extreme Pressure".

https://en.wikipedia.org/wiki/NLGI_consistency_number

[Shiny]

As I understand, greases called "extreme pressure" contain solid additives that reduce friction when there is insufficient speed to build up a fluid film between the interfaces. Materials commonly used for "dry lubrication" (teflon, graphite, moly disulfide) are added to reduce friction during start/stop and/or at low rpm for bearings that have to run over a wide range of rpm. Every time I see black grease, I assume it's loaded with moly disulfide.

I'm sure there are industry-standard ways to measure the effectiveness and durability of those EP additives but I have no idea if there are standards and/or "grades" for that. I would expect so, given the industry pressures to have "alternative sources".

I'm also sure there's more to it than just adding magic dust. There would have to be other additives to keep those EP particles suspended and avoid them causing degradation of the oil or thickeners or chemically reacting with wetted surfaces in the presence of moisture. Just read a few threads on here comparing motor oils and we can imagine how complicated the formulation chemistry gets with greases. I have no experience doing that but much respect for those that do!

[dmorg1]

It looks like most manufactures list if the product contains the EP additive just before the service weight on the product package.


(Castrol Pyroplex Red EP 2 Grease)




Here is some information from my local industrial lube supply website.

Extreme Pressure (EP)

Greases with Extreme-Pressure (EP) additives are ultra-high-performance greases formulated to lubricate, protect, and act as a sealant on machine components or, in general, heavy-duty applications that specify the need for an Extreme-Pressure semisolid lubricant.

Greases without EP additives struggle or fail to stand up to heavy-duty tasks including the lubrication of highly-loaded bearings and other industrial and/or heavy-duty tasks. Extreme-Pressure additives provide first-rate protection to machine components and vehicles operating under extreme service conditions -- these additives allow for increased resistance to rust and oxidation as well as vastly improved shear stability (when compared with non-EP greases).


Extreme-Pressure Greases generally outperform basic greases in all areas, though some are more suited to specific applications such as high load, moisture-heavy, or high speed machine operations. To determine which Extreme-Pressure Grease is ideal for your application, refer to OEM specifications and the Product Data Sheets listed on each individual item page




Dave