Truck stalling

[Alucard5644708]

Hi all, I have a 2004 Chevy Silverado 1500 5.3 v8 4x4 ext cab. While I was driving with no extra anything going or running.

 

But when I come to a stop or slow down to a stop, my volt meter will begin to drop and my lights will flash. Then my truck will die.

 

I have replaced the throttle position sensor and harness. The alternator and battery were tested and are good.

 

Is there anything else that I can look at? I have heard of the grounds, but can not find them. If anyone can help me out or point me in a direction. It would be greatly appreciated.

[O_J_Simpson]

intake gaskets.

[Alucard5644708]

Also to state, this didn't happen until I reset the oil. Where it said "change engine oil" which it hasn't even been 3,000 miles yet.