1/4 dose of lubeguard red transformed mine from “I can’t find 4th so we’ll take neutral” to “Lexus smooth,” caught early. I also put 1 qt of amsoil signature ATF for every 3 quarts of valvoline ULV, for a *slightly* heavier mix. Full or even half amsoil LV at that time was no good - too thick and it messed with shift timing.
For anyone in Australia, Penrite now has a ULV too specifically for 10R/10L transmissions.
Might try it in my sister’s Focus with the 8F24 seeming it’s a little cheaper than the Motorcraft fluid and made locally instead of imported from USA.