my understanding is that moly is sticky, and won't be as runny to leak out of the birf seals.Whats with the Moly & non-Moly grease??? I have used valvolene syn for years on all the zircs (dif car) with no issues. Stuff even says for U-Joints on it.
regular lithium probably works its way into the needle bearings better in everything else.
actually greasing is more important than what type of grease.