Oil filter change vs oil change

Any known 'SLUDGE' engine needs a few mods to keep the oil from gunking up the valvetrain. Somehow the oil gets trapped up in the heads and valley due to piss poor engineering. Those you MUST change the oil at 2,500 or so but that only helps a fraction.

All Jeep 4.0L run hot due to piss poor designing. The radiator is too small for one. The head traps air in the rear of the head and you must lift the rear end up high enough to get that air to 'BURP' out. The coolant overflow system was designed in a Kindergarten class. And if you do the 4.2's crank swap for a stroker 4.5/4.6/4.7/5.0 Liter that heat is even worse. You should add an oil cooler with its own fan and thermo switch.

The 5.2 and 5.9 Magnum's oil pumps SUCK, no pun intended. The bypass valve sticks open when real hot and as you are doing 70 MPH, the idiot light comes on and the crank is eating bearings. Does not matter what type oil you use. Drop the oil pan and put a Melling HV pump in. Where the type of oil matters is sludging in the heads and lifter valley. Hot oil gets trapped and bakes. After replacing the crap oil pump, add an exterior oil cooler.