Brought my 98.5 from Colorado to Oklahoma. Along the way the voltage regulator in the alternator went out. One battery got warm and vented a concerning amount of fluid. (Type 31 batteries. Problem battery disconnected). Any ill effects of running a single battery until I swap alternators and get new batteries?

Nah. 

I had one battery die and my truck wouldn't run. Maybe it matters wich battery

Nope the batteries are wires in parallel.

Are you sure it was the voltage regulator? Often a bad crossover cable will present like a bad voltage regulator. 

 

Which battery overcharged?

8 minutes ago, Me78569 said:

Nope the batteries are wires in parallel.

 

Exactly, unless there are other issues going on as well. 

I must have other issues one battery was under 12v truck put out over 14 replaced only battery under 12v.

 

Cleaned cables before replacing battery didn't fix it. Finally replaced low battery that was over a year ago.  No issues since

5 hours ago, Evan said:

I must have other issues one battery was under 12v truck put out over 14 replaced only battery under 12v.

 

Cleaned cables before replacing battery didn't fix it. Finally replaced low battery that was over a year ago.  No issues since

 

How far under 12V was it? Which battery?

Drivers side.

I dont remember how far under. 

You could let another vehicle charge it for 5 minutes or so truck would start then die within minutes. 

 

Batteries showed same voltage hooked up to truck over 12 the bad one alone under 12.

 

I remember this night well I was alone a few blocks from Walmart so I bought one batter and found out just how heavy a battery is to carry 

 

What I should have done was move passenger battery to driver's side to see if it would then fire up and run. Or maybe just unhook the bad battery 

Haha... few blocks is a long ways to carry a battery :-)

 

It should have still ran with the bad one hooked up thou, interesting. 

It took like 8 people to push it out if drive through line. 

They ended up letting me have my order free. Lol  this before I had a truck full of tools.  One trip to Walmart for a volt meter then back for a battery. 

If the green field wire happens to find ground, it will charge yet but full runaway mode. This will cause the boiling out of the batteries. If the blue wire shorts to ground then the PCM will fry instantly burning the circuit board out. 

You need and want two batteries in Colorado.....that grid heater draws a lot when it’s cold ....I’m in Wyoming so yeah