Type f contains more anti foaming additive than dextronIII.type f higher viscosity thicker fluid.type f has more industrial detergent content.you may think it all looks and smells the same but its not.dextron cost much less to mfg.and doesn't go through the same lab test.a co worker peed in the sample cup filled it with dextron and it still passed the labs spectrometer and tritation test.i wouldn't use it I've seen it foam so bad the beakers had to be sonicated just to make enough liquid to test it.then it sits in mix tank for a week so I can be bottled