Yesterday a 2005 newer body style Malibu with the 3.5L V6 Engine was brought in to the shop for brakes and the fuel level sending unit. While inspecting the brakes we discovered a oil leak. The oil was leaking pretty heavy. We discovered that it was coming from the oil filter area we cleaned up the area where the oil was coming from and started the car again and we found that it was coming from the oil filter housing gasket.
GM did horrible job on the design of this. The housing has 3 bolts in it and one bolt is behind the A/C compressor and this hole is slotted. That bolt behind the AC compressor tricks you because it looks like it can be loosed because GM slotted this hole so you only have to loosen this bolt. We made every valiant attempt possible to loosen this bolt and we failed and wound up loosening the AC compressor bolts and removing the belt to get to the bolt.
If you don’t believe me you will more than likely find out after you try to remove the bolt without removing the compressor and you are probably going to strip the bolt.
Lesson Learned: Loosen the compressor and remove the serpentine belt off the idler pulley to all full access to the third oil filter housing bolt behind the compressor.
once you get it off replace the gasket or seal it up using Permatex on both sides where GM had sealant on their gasket and stick it back up there after you clean off both sealing surfaces.