Suzuki: side kick wont go over 20 mph, suzuki sidekick, automatic transmissions

Question
i have a 1995 suzuki sidekick that wont go over 20 mph . has power. 130,000 miles . could be trans related . doesnt run with a miss . doesnt stall out . runs good . trans solenoid?

Answer
Is this an automatic that won't upshift?  If so, then it's quite possibly a solenoid issue.  I, unfortunately, have stopped doing anything with automatic transmissions more than twenty years ago, and have no literature about Suzuki automatics and their issues, and can only offer generic, and quite possibly out of date suggestions.
scotty