The thing about that accident was I wasn't really over weight. That whole trailer and load was only 8000 to 9000 pounds
Madcow, 1500 Avalanche has a max towing capacity of between 7300 to 8000 lbs. The coils could not handle the load and began compressing and unloading. Your shocks could not dampen this so it builds.
Hope your arm has healed.