There are many oil seals in that vehicle, need to know which ones you changed.
Where is it leaking from? Could be front or rear seal or coolant lines Did you change gasket when you changed fluid?
The ball very seldom is the problem it is the springs and cap washers
And you still have a skip? Probably a bad injector.
Check the brake light switch.
Are there still seals on pier 39 in Sanfransisco
Master Cylinder internal seals are failing. Replace the Master Cylinder before you have an accident when it fails permanently.
Cooling fan could be faulty or radiator could be clogged or have slight leaks in it .
check the heater core stopped up radiator
When you fitted the new cartridge in did you use any grease on the seals. plumber's grease or white lithium grease helps assembly and stops many small leaks.
Was that the only code that caused you to replace it? Do you have it close enough to sense again.
seals are still around. they are not yet extinct but are becoming extinct
i have to same problem with my sierra ive changed the filter and it still leaks, i was told that its the oil filter adapter you can get one at autozone for about $20