2005 Rattling Sound and only RPM at 5 ahen sitting Idle

[KingdomTransport]

This is the right front top of my engine.  I have never seen oil leak from here.  There is that low power idling at 5 rpm when i am sitting still with a rattling sound towards the middle back of the engine still going On even after I have replaced both fuel filters. Oil and transmission fluids show full on the stick.  It now gets quiet when I turn on my PTO.  When I used to turn on my PTO, it always made a whinning sound which would let me know it was engaged On, but it doesn't make that sound anymore. It drives and pulls fine with no codes but the rattling sound when I come to a stop is definitely different with the low 5 RPM. What do you think is happening?

[Mack Technician]

Assuming you are not leaking above what is pictured...........your lower exhaust studs are open to the crankcase. Drilling’s go right to oil and come within a hair of touching push tube. Only fix is to remove lower manifold stud, clean threads with solvent and reinstall with thread sealant..... or just live with small leak. 

Edited September 22, 2018 by Mack Technician

[Mack Technician]

Noticed you still have the choke-collar exhaust manifold on your bulldog..................... Best time to reseal those exhaust studs is while your throwing that manifold in the recycle bin.