4.0's inaccurate dipstick

I wouldnt run anything above the upper fill line to be honest. I have seen what excess oil (even a bit above the top line) can do to a motor.... blown seals etc.

I personally, pull the plug, let her drain while i lube the driveshaft u joints (3-5 min) then fill her with a 5 qt jug of mobil 1 full syn 5-30... maybe an 1/8th in below the top fill line after its all said n done.

 

5.5 here on a 13. That synthetic is a mofo to read after a change. That is all