Reading thru my notes I found interesting filter and grease data for you to read.
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Testing revealed that BLG provided excellent field performance compared to the G-version grease. The testers observed no sign of biodegradation in the lubrication systems during operation, indicating that BLG products will only biodegrade under certain environmental conditions. To assess this experimental BLG, a field biodegradation test was conducted at the bioremediation site at Fort Hood. The BLG test results clearly showed more rapid biodegradability, which occurred within a 6-month period, compared to G-version grease, which showed extremely slow biodegradability for many years.
In 2008, the MILSPEC was revised to accept BLG as the GAA grease. The revised GAA specification, MIL-PRF-10924H, included an additional biodegradation test and a higher acceptance limit for load-carrying capacity than the MIL-PRF-10924G standard. As a result, BLG officially became a new “green” GAA military product.
While BLG’s formulation is not the same as the old G-version GAA grease, they are comparable in performance and fully compatible. Existing G-version GAA grease can be easily changed over to BLG without needing to extensively clean the lubrication system. During the changeover period, both greases can be used in Army vehicles and equipment until the G-version GAA grease is exhausted."