There has been a lot of discussion on the Allison approval list. The only way Allison will approve a fluid, is by having a company pay them to test on their shop transmission, which I heard is not readily availabe. Amsoil Torque converter Synthetic ATF has been tested by outside labs and meets and exceeds the TES 295 spec. They certify it and warranty it. Many of the products listed as approved by Allison, are just the overseas name for the product. I was told by a tech. at an Allison booth, that the Amsoil product was fine, as long as it is certified to meet the TES 295 spec.
It is a lot like the oil in the cars-GM, Ford, Honda, BMW, etc. all recommend using their products, but also state that any other produc used must meet xxxxx spec.
Look at the price of Transynd--made by Castrol--both companies need to make a profit.
04 SeaBreese LX 8341 / Workhorse W-22 / GM 8.1 / Allison 5 Speed / Brazel's ULTRAPOWER Upgrade/Taylor Extreme Service PlusCables/DIYCAI
06 Honda CRV4/SE/all wheel drive with Falcon II / Roadmaster 9000 Braking System