DESCRIPTION 1981 Progress Industries Liquid Transport Trailer (GP4816, Unit 106555), 1981 Progress 5,800 gallon, conical stainless steel liquid transport trailer, tandem axle, spring suspension, Honda GX390 electric start gas motor, Banjo self-priming centrifugal pump, side ladder, 11R24.5 tires. Serial Number: B31574 Notes: Pinhole leak.