I just parked on as level ground as I could find. Measured from where the spring holders are welded to the frame on each side. Three points, from and rear and where the connects.
Right side if trailer is exactly 1/2" closer to the ground.
Bought new January of 2015. Just replaced all four tires and it was doing the lean before as well.
I don't see any cracks, bendsor problems with any part of the suspension. Four leaders on each spring.
Will be towing 7 hours tomorrow, hope it's not an issue but I believe it's been like that since bought it.