ksg5000 wrote:
Don't think I have ever seen a crack in the crown - would think that's a pretty good sign that there is a significant structural issue. I would contact dealer and mfg to discuss - if possible get a new unit as a cosmetic fix of the crown may not hold up.
The exterior fiberglass sheeting is very thin and will crack anywhere if the underlying structure allows movement. I agree that the crack is the result of a structural issue but it doesn't have to be significant or catastrophic to crack the exterior sheeting.
Correcting this problem for the long term will most definitely require a thorough inspection and correction of the underlying problem and structure, this will result in replacing all or part of the roofing material.
When speaking with the dealer or manufacturer I would not accept a cosmetic fix as it will only crack again - I do have personal experience with this.