I was a Ford tech for 25 years.
These engines are designed for low octane fuel.
The high octane fuel is "slower" burning. This will actually create carbon deposits in the combustion chamber.
These carbon deposits will flake off and jam a valve open causing engine damage.
I have seen it happen several times.
I've had bad luck with the AGM batteries. Also, their reserve capacity is way lower than a lead acid battery.Reserve capacity is for starting batteries and has nothing to do with the number of deep cycles a battery can withstand!
I think you're confusing Cold Cranking Amps and reserve capacity.
The batteries (acid) I bought have 180 minutes reserve capacity each.
You would need to remove the steering gear box to check for any broken off bolts.
The bolts probably got loose over time, causing them to break.Or, someone must have worked on the steering and left the washer off.
Make sure you go back with the OEM bolts and washers.