so guys how do you do a flush on a zf ? just bought the car with 131k and still has the plastic sump .... so looking at doin the steel sump convo and getting some gulf western syn trans atf ...have also heard Castrol transmax z does that box aswell ?? ...... but whats the best way to flush the old oil out of it ? have heard of leaving the old plastic sum on it and leaving the old fluid to drain for a couple of hours then fill it ...run it for a while the drain again this time changing to the new filter and steel sump and refilling it .... is this correct ?
