I have a 1987 o day. It has a westerbeke 10hp diesel engine. The manual calls for type a or dexron ii trans fluid. I went to pep boys and wm for the fluid and was told they don't carry that type. Since the manual is from 1987 has the fluid name changed ? Have they improved on the fluid and changed the name to dexron 3 or 4 or from type a to b or c. This is all new to me. Any suggestions will be appreciated. Thanks.