And what kind of oil are you using? Mobile-1, castrol, Havoline,etc...

 

It's probably something you are doing if this is happening on a second 3.9. These things are about bullet proof if taken care of properly. I'm guessing wrong type, amount or weight of oil.

 

i was using an expensive carquest brand synthetic oil. and i was using a 5w 30 oil. now i guess this never crossed my mind before not being oil weight savy, but if i used a thicker weight like a 10w 30 would that make a big difference??

 

3.9's require 10w-30! I'm guessing that that could be the start of your problem. Change out the oil asap with 10w-30 and see if that helps.