I have a F-150 with one of those "less than perfect" 5 speed Mazda manual tranny's. It shifted like sh*t with the factory fluid, Mercon, in any temp. I changed to Schaeffer's #204S Mercon ATF. It shifted better, especially in the cold temps. But in any temps above the mid 30's the shifting quality left a lot to be desired
. I tried Mola's SF SynchroGlide, a Group IV and Group V, which is thicker than ATF plus it has EP and AW additives that ATF doesn't have. The shifting quality is much better even at 18*F temps and also even at 60*F temps. The tranny is still a p*ss poor design but at least the SynchroGlide made it more pleasant and usable. A big thumb's up to MolaKule to design a fluid that will help overcome p*ss poor engineering
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Whimsey
Whimsey