Pedro, there's been a lot of talk of the different flush machines on the BITOG forum over the years, but I've never paid any attention seeing as I don't drive a slush box.
Might pay to do some searching/reading here ATF, Differential, Trans, Brake, P/S - Bob Is The Oil Guy and here Mechanical /Maintenance Forum - Bob Is The Oil Guy
Beware, their search engine is crap. Best to do a search using Google.
Autospeed have an article outlining the different flush techniques here Browser Warning

