Mike, I had the same problem with my 1999 Montana with the Dewald system when retracting the slides. Basically there are two solenoids, one for extending and one for retacting the slides. Mine continued to run for a time upon retracting the slides and then shut down. The solenoids are the same part number, just wired differently. By reversing the leads you can bypass the defective solenoid until it's replaced, or pump them in and out by hand.
This link will take you to the Power Gear website where you will find information on part numbers, adjustments, and trouble shooting the system.
http://www.powergearus.com/
Good luck,
Don (also retired SBC 6/01)