I took mine to a hydraulic repair shop. They installed a new seal, with the jack still on the trailer. The RV dealer (warranty work) was going to remove the jack, send it to a repair shop, then reinstall the jack. "It takes about five days", he said. We said "can't we just drive to the repair shop and get it fixed without removing/reinstalling the jack"? It took about 1-1/2 hours to replace the seal.
Chris and Pat
2016 Ram 3500 Cummins Aisin Dually, 4.10 axle, Auto Flex Air Ride Rear Suspension, Pace Edwards JackRabbit tonno, Transfer Flow aux fuel tank, B&W RVK3600 hitch
2017 Cedar Creek 36CKTS, Disc Brakes, 17.5"