Replacing my truck batteries, how important are CCA numbers?

I know I’m going to get jumped on and flamed like crazy but here goes. Just for the sake of providing correct information and safety, it is correct and safer to disconnect the ground cables from batteries first, and when reinstalling the grounds should be connected last. And definitely a solar battery minder. Flame on.

 

No flaming, just curious, why ground not positive? Realistically, positive and negative are fairly arbitrary distinctions when speaking about dc systems, and while many things are polarity specific, it hardly makes a difference which is still connected.

(Also, while you may be correct, on my truck specifically due to how batteries are installed, positives MUST be disconnected first, cant really get to the negatives before the positive, if i reversed the batteries, there would be quite a bit of arcing potential removing any positives before all grounds were out, but if i did that, the potential for any wire coming loose and burning my truck to the ground would also be significantly higher)

 

Woodland Park. Although most people live out of city limits up here. Most everything that's not National Forest or a ranch now has a house on it.

 

The idea on removing the ground first is that if you bump something grounded with a tool while removing a positive, you'll get one hell of an arc unless the battery ground is already removed.

 

Be careful after killing the batteries like that. I had 1 go to ground on me and got real pissed off. Got super hot, puked all the water, and pissed my alternator and drained the other 3 batteries. This happened shortly after I deeply discharged them leaving lights on all weekend ‍♂️

 

You pucker up quick when the wrench contacts the fuel tank. My 9/16" ratchet wrench was never the same after that doozie. Always ground off first, on last.

 

Add a wedding ring touching the wrench that gets arced.