So my 2003 Signature which I have owned since new, I was told by the main Allison dealer here in the Chicago area , needs to have a new transmission installed. (Ouch) The transmission is a Allison HD4000MH and the engine is a Cummins ISX525. My coach has 60k on it and I have always stored it indoors and heated indoors during the winter. I have the coach serviced regularly by my diesel mechanic and had the oil in the trans changed at least twice since owned. I know that the last time the trans oi