Got an old ranch truck thats a 94 dodge diesel and everything was working as usual and then all of a sudden one of the batteries had the tops blow off spraying everything with battery acid. Thought it was just a random bad battery at first but after putting another one in she started surging and acting funny and we were afraid we were going to pop another top so we ended up towing it back. Has anyone heard of something like this happening before and what ended up being the problem?

Yeah, back in the early 90's I had a battery go dead on my '84 ranger. It was a manual transmission, so we push started it and got it back home. When I tried to crank it at home, it exploded. I think it has to do with being an old battery and leaking hydrogen gas... the spark probably came from a poor connection at the terminals and boom.

Lead acid batteries can form hydrogen gas if the solution inside gets low and the electrodes are exposed too much air, I believe. Then any short circuit in the battery that sparks it can blow off the battery cover or blow it out. I think an overvoltage from a bad alternator or generator can make this more likely.

some additional info from my buddy who was actually driving it at the time

it started to rev down like it was going to die, I went and started giving it some throttle and it wouldnt rev all the way up, seems like not all cylinders were hitting, then i started to limp it along, had zero power and was rolling thick grey smoke. the battery gage kept fluttering too. finally just died. when we were towing it back the flashers would come on and off, and alarms and dings. like it was possessed. dad told me that a week ago he realized it had overcharged the battery and thought the alternator was going bad, he took it over to the mechanic and they changed the lead that connects both the batteries, thinking that it was just a connection issue. so, it could have been the alternator i guess but it escalated to other problems too