If you are running that gear on the street you need a GOOD synthetic gear lube. If you live in a warm clime year round, you can use a 70w140. If it gets cold use a 70w90...preferably a GL-6 gear lube.
OP, I put Red Line synthetic gear oil in my last street Dana with a chrome cover and that rascal leaks out between bottom of the gasket and housing, even with Mopar gear lube silicone
That cover never leaked with regular gear oil in all the other rear ends I have used them on
I'll probably end up putting regular petroleum based posi gear 75x90 WT oil back in it with the posi lube additive
