Have you checked your shackles. I noticed my right front tire was at an angle. I placed a fairly straight 2" x 4" against both tires on each side. The right side was 3/4" different. Turned out that the shackle had worn through but had not totally released. The other shackles were worn badly. It cost me $160.00 to have that one replaced and I watched them. They replaced the dry shackle with a wet shackle and left grease all around the zert fitting. I went home and ordered parts to replace all four. When I pulled theirs down, there was absolutely no grease inside. IIRC, when you install wet shackles, the hole to allow grease inside must be in the 3:00 or 9:00 position, never on the top or bottom.
FWIW, I did not have very many miles on the unit. Whether this is your problem or not, it is well worth your time to place shackle checks on your check list. If one does wear through, the axle spring will release and get driven up into your camper possibly causing considerable damage, if not to your camper at least to your self esteem.