I cannot imagine a 1/2 quart low would cause it to slip. unless maybe you were driving on major inclines all day.

i think most trannys lose 1st/reverse because they share a planetary gear and they are the lowest(highest loaded) gear. On old chevys the lip seals would get hard or the soft shifts would wear down the clutches/bands and then you would start to notice a delay as you engaged reverse… eventually leading to major slippage for 1st/rev

I was told our tranny is a GM unit out of france. I really hope they use orings and not lip seals… I worked on Toyotas for a few years and their autos were almost bulletproof because their orings would get hard but rarely leak like a lip seal does.

does anyone know what kind of seals the vx has in the clutch packs?

btw, i bought an interceptor from Tone just to get a crisper shift so it would not wear down as fast. i noticed when i got the vx it seemed to have kind of soft(designed slippage) shifts. The interceptor is kind of a bitch to adjust since the gain is not right... you can only turn the pot about a 1/16 of a turn before the shifts are too harsh.