Almost every electrical-related post on this forum mentions replacing the OEM battery terminals. I'm wanting to know what the failure mode is of the terminals. What breaks? What is the weakness?

As far as I can tell, mine stay tight and conduct electricity.

 

the acid and corrosion wicks its way through the wire turning it from copper to a white green residue powder that does not conduct current.

 

H3/H3T OEM Battery Terminal Connectors are defective. They are made from cheap white metal and rely on one nut on a integrated bolt to slide on a wedge like shaped clasp to tighten for a good connection. That works for about 2 uses until someone trying to get a better connection over-tightens and crushes the wedge making it impossible for the connector to properly tighten for the solid connection required from that point on. Once your Battery connection is intermittent the PCM and BCM get conflicting information from a bunch of different voltage inputs they are monitoring and things go south.

Usually happens first time the battery is replaced or disconnected. Not a matter of if, only when.

Corrosion is the enemy of all Battery Terminal Connectors.

 

Keeping my fingers crossed, and bought new battery terminals a while now (hasn't been installed), but the truck still has on the OEM ones on. No electrical problems so far.