can anyone confirm that this is the OEM engine oil filter for our GS350?
also, do I need to purchase anything else to replace oil other than oil & filter?

http://lexus.sewellparts.com/accesso...2013/2543.html

 

you should pick up some oil drain gaskets too

 

Hopefully you already found your answer, but yes. That is the oil filter you need along with oil (the filter from the dealer comes with the gaskets you need). You will need a 10mm to remove the filter cover and a 14 to remove the drain plug. You may also want a filter wrench to help get the filter off.