Have you ever changed the two small o-rings on the shaft under the canister lid? They will get hard and no longer seal well and should be changed every third or fourth oil change.

Not in the filter change kit but are available at the dealer or any big box parts place as part of a metric o-ring assortment.

I'd change the little o rings Rocky mentions. After that, if the rattling persists, I'd suspect the oil pump being worn. If that is the case then a rebuild is in order. I'd just drive it and save my money for a rebuild.

I don't know if it is possible to change the oil pump without doing more to the engine or not. I'd suspect the pump may be changeable just by dropping the small oil pan.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.