Thanks for the move. I hoped you would have a place for me somewhere. There simply isn't much about these, and they seem to be closely related, with the only difference being Barth or Dynacoach.

Here in the land of orphan coaches we try to help. Barth used the Oshkosh chassis from about 1988 for the longer Regal models. Prior to that, they used an extra tag axle for the heavier models. The Oshkosh chassis was rated at 18K lbs compared to the GM at 16K.

I found this parts catalog a while back, you may find it useful:

https://www.barthmobile.com/eve...1087061/m/5873935487

I have seen a service manual somewhere but not sure we have it here. Good luck with your coach.

Here is a link to the service manual,(large pdf file!)

http://www.cdr-roc.com/89JD/89-JD-Chassis-manual.pdf