MLS = multi-layer steel..... which require a very fine machine surface on the heads and block to avoid leaking..... they're not for everyone unless you have a machine shop with much better than average results.

The reason I said the head gaskets may be blown is because the upper radiator hose is very tight and a heater hose ruptured - perhaps from steam, but also likely from combustion gas pressure. If the head gaskets haven't failed, they soon will as Eddy said.

What could cause the head gasket(s) to fail? Likely a clogged radiator - also as Eddy said.

All speculation until the diagnostic and forensic work is done.

3.0L engines blow head gaskets if the cooling sustem isn't kept in good condition - radiators and cooling fan clutches are the main culprits.

Composite factory gaskets are fine..... and preferred by me...... even with moderate amounts of forced induction.

Frank