Sorry for the silly questions. At the moment I'm operating in thew dark with no service manual or owers manual.

1996 Cherokee 4.0 ltr engine: The oil drain plug doesn't seem to have a crush washer, but a rubber washer. Is this the way it's supposed to be?

And I have noticed a square inlet on the air filter housing and just in front of that another square hole - same size - on the radiator support just behind the left headlight which is covered by a plug held by two screws. After looking through the grill assembly, it seems more air could be had by removing this plug. Has anyone done so?

 

Yes, that's how the drain plug should be. I'm unsure about the airbox, though, I've got a Cold Air Intake. Check your PM inbox in a minute.

 

I did it when i had my air box. I now have a K&N but yes it can be removed. I dont know why but some models have a piece between the airbox and to that plastic plate. Good luch in removing it unless you have a small dremel. I didn't notice any improvement, but more cold air isn't going to hurt.