My 4710 had a real sticky tilt when i first got it. I had the dealer lube it when it was in for service, and now its perfect. I would think pulling a cover off and spraying lube in there would fix it.
My 4310 was like that and eventually got stuck in the down position. I took it in and there was a service bulletin about this problem. They fixed it and it has been fine for about 70 hours. It stuck at 40.
My 4410 had that problem from the get go. There was a service advisory on this. They put new parts in it and the tilt works OK now but there is still a lot of play in the steering wheel itself.