So as previously posted I had a 2002 Hyundai XG350 that was having a transmission flare. I began experimenting with different ATFs and eventually fell into trying some type F in it. This worked great for about 300 miles, but began giving weird delayed and jerky shifts. After this I then flushed all 10 quarts out with Maxlife, then added 2 bottles of lubeguard black highly friction modified atf supplement. This actually appears to have fixed the problem. It has been just over 1.5k miles and it has not returned. Also a reverse engagement was mitigated too. So although that is probably a pretty large overdose of friction modifier, it seems to have worked for my application.