Check the axle tag to determine its weight rating, then do the same for your springs.
Our Montana had two 6,000 pound rated axles, but the springs from the factory were rated at 2,500 pounds each.
After two spring failures on two different occasions, I upgraded the springs to 3,000 pound rated ones along with upgrading tires from E to F load rating.
Used to have severe tire issues where inside tread on all four tires wore excessively. The spring upgrade also fixed that issue.
02 Montana 3250RL upgraded a bunch
05 Ford F-250 6.0 Bullet Proofed