373 Axle question

We purchased our 373 from Tuscon AZ. Pulled it to SoCal and setup a 5k trip across the USA.
Came home with 22 squawks for repairs. The biggest, is the axles. Tire wear on the outside said something about a bend axle.
During the trip, The left rear tire left the axle as all the studs broke. Could it have been a fault of not checking the nuts for torque? Yes. But still.
That fixed and we were back on the highway.
Heartland did replace the axle over the spring. 2 months in the shop.
Now to the trip up north. Tire blowout in Selma, Ca and a call out to the fire department that responded. Some of the underbelly covering is melted away and will need to be replaced.

Also, the main door is opening during transport. Locking and putting the handle over the door is ineffective.

Is anyone else experiencing axle problems on a 373? 2 7000lb axles under a 18,000lb rig????
Cal
 
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