Engine stall

2002 HD 4x4 8.1 Allison with ~77,000 miles on it. Within the past 3 weeks my engine has stalled and then restarted by itself (once at a light I had to put it in park and re-start it).
I have noted that the first two times were in the same location, coming up to speed (~60 mph) merging on to highway. Engine stalled, battery light came on. Dash lights did not flicker they stayed illuminated. After ~3 seconds the engine came back to life and off I went. The next time was on a back country road, ~35 mph slighlty bumpy road. Same symptoms. 4th time was at a stop light, idling fine and the the light went green, stepped on the gas and it died! Threw it in park and started right up with no hesitations. Getting worried that something is about to give out and leave me stranded!
One note, the DIC just turned on to change the oil (after the third event, for the first 2 events the light was not on). Soon after the oil change light came on, another message com on telling me to check the oil level. So I am thinking that maybe I have a smart truck and it will shut the engine down when there is a loss of adequate oil pressure / volume. So I added oil to the appropriate level and it happened again this morning. Same back roads around 35 - 40 mph.
Not sure if I need an code scanner to see if there are any fault codes or not. But each time the engine shuts down while showing the battery toruble light and all interior / dash lights remain on with no flickering.

Any ideas or checks I can do without buying a code scanner? Or paying the dealer?