Originally Posted by jksport12
Your battery has nothing to do with the stalling. A car will run off just the alternator. Battery is mostly used for starting and powering aux lights and such.
Not true with a TJ, its alternator runs off of and requires 12v from the battery, it is not "self-exciting" like all the older generators were and some other alternators are. If you disconnect a TJ's battery, the engine will run only until the magnetic field in the alternator dies in a minute or two max and then the engine will die. The battery in my wife's Grand Cherokee's died and I had to jump start it 6-8 times during the drive to the battery shop 3 miles away.
This is why a TJ can't be bump started if its battery is truly dead. It can only be bump (push) started if its battery still has enough juice left to power the alternator.