What is "too slippery"? GM has gone to a new standard for transmission fluids called Dexron VI. Though it doesn't specifically call for a synthetic fluid, to tmeet these standards will essentially require at least a synthetic blend, and probably a Group III synthetic. If the above statement were true, why would GM be headed in this direction?matjow said:"Synthetics fluids are great in motors because everything is metal to metal where you want the least amount of friction you can get.
Not the same in a transmission where you have friction material such as clutches and bands and lockup clutches in the converter. You can get things too slippery and have issues with those items."