I prefer the amsoil fully synthetic grease, I usually give each fitting a pump or two of grease at each oil change.
AMSOIL GH Series Extreme Pressure greases are qualified against the highest grease standard, NLGI GC (wheel bearing) and LB (chassis), and are designed for heavy duty applications. These greases are composed of synthetic base oils and lithium-complex thickeners that provide the film strength, shear resistance, and mechanical stability critical to high load protection. This combination excels in high and low operating temperature ranges by providing excellent oxidation stability, high temperature dropping points, good low temperature torque values and good low temperature pumping capabilities. The GH Greases are compounded with oxidation and corrosion inhibitors, effective oil soluble EP additives and molybdenum disulfide (moly) solid EP additives for all around protection in severe conditions.
The presence of moly provides an extra measure of protection in shock loading situations common in both construction and agricultural use. During heavy shock loading, the lubricant film between metal surfaces can be temporarily ruptured, but moly remains intact to prevent metal to metal contact which could cause equipment damage. Moly also assists in dirty environments or when proper re-greasing intervals are not followed.
AMSOIL's top performing lithium complex thickener system provides excellent water resistance as identified by the ASTM D-1264 water washout test. Therefore, even in wet conditions a lubricant film remains present to protect equipment against wear while the corrosion inhibitors prevent rust. AMSOIL GH greases adhere to metal and are shear stable during severe mechanical activity. These features mean the grease does not thin during operation, but rather it maintains its consistency and stays in place to provide good lubrication.