Welcome to irv2 and the forum.
Here
is a link to find all TSB's that may relate to you coach 1998, the 1999 may have links in it that can apply to your coach, There are also bulletins on same page.
http://www.irv2.com/forums/f258/newb...v2-201159.htmlThis link will give you info about how to get around irv2 and a irv2 search engine where you can input your question about gear box and you will get old threads maybe with the information you need.
All the links below in my signature have info for your Newmar. We also have a section of older Newmars owned by members
QT's # 3.
In
this link you will find salvage yards near bottom of the link.
Enjoy the forum and safe travels when you get it fixed.