Source: The Risks of Using EP Additives - Noria Corporation I found AMSOIL in our NHW11 transaxle resulted in high copper content. The copper content after 53,000 miles was lower than after 7,000 miles. This short video explains why an AMSOIL might 'eat' the copper. Our NHW11 transaxle has at least one bushing-style bearing plus all of the links in the silent chain. Put in a copper eating additive and it would wear out quickly. The same risk is in the NHW20 transaxle. Bob Wilson
So, I put in Castrol as I found a link on here. Does that have a high Copper content? Which leads to, what are most putting in their CV transmissions? TomK
When running a non-Toyota, transmission oil, it makes sense to do an early sample and see where the numbers are going: test the old, replaced oil - about 25% will carry forward test the unused replacement oil - so we'll know the initial metrics test replacement oil after a short interval, 5-7,000 miles - see if a problem is developing That is what I did with AMSOIL and found the problem with copper loss early. When we use a non-standard part, we have to assume we're the new 'lubrication engineer.' That means we take samples and have them analyzed. The worse thing is to wait for the "Uh Oh!" moment especially after bragging about 'I used xxxx and . . . ' Without metrics, it risks being wishful thinking. Bob Wilson
