Just completed my second trip with our first 5th wheel. Got home and chocked the wheels. Started extending the landing gear and when weight was put on, the gear slowed to a crawl and then stopped just...
No funny noises like a gear slipping? If not, and you're sure you have decent voltage (you do have the truck running don't you), I'd suspect an electric motor problem. You should have a crank handle and access to manually crank it up.