Car Battery question
 

My truck was had to start today, and the battery had been in it for almost 4 years so I drove it to the store, and bought a new battery. The old one had expanded and the sides were buldging at least 1/2 inch on each side.

What would cause that? Other than age?

Over charging. Thats dangeroos.

Beat me to it. Have your alternator tested. Parts stores like Autozone will test it for free, you just need to take it off the truck and take it into the store.

Also need to see if the voltage regulator is in the alt or seperate.

No I thought of that, its charging between 13.5 and 14.5 while driving

Trusting the factory gauge = fail. Your battery was slowly melting so its most likely the problem. Unless your using an aftermarket gauge in there while driving the only proper reading your going to get is by using a multimeter and revving the engine.

multimeter

Good deal

could todays temperatures (105) been the culprit?

Normally that is sign that the a battery was frozen, but I think I've seen an overcharging condition cause this as well.

When did this occur? Is it possible that this was like this during the winter and you just noticed it now?