TODAY is a Great Day to visit our Store and order the parts you need for your truck ! ! !
Go to your wrecker, or towing company, see if you can find a leaf sprung van, buy the springs, put 3 leafs out of the van springs in to replace 2 of yours.
I'd say if thats the only crack on the leafs remove the bottom two leave the over load and add air shocks to bring back the load capacity
How does or what causes something like to happen?