Got an 05 Malibu as well. Got the 3.5.
Have had a lot of minor issues for the most part:
-The turn signal sockets I think I finally have cured.
-Power lock buttons inside flaky
-Power mirrors are flaky.
-All buttons have that painted on finish...which wears off quickly - Very cheap of them.
-Interior plastics have all done poorly, major discoloration/staining
- Cooks any battery at the 3 year mark. Doesn't matter how cheap or how expensive or how rated... 3 years, and need to buy a new battery... Just too much heat in these crapped engine compartments... that isn't just a Malibu issue, but I can pretty much set my calendar to this one's battery failing.
Paint is subpar.
The major:
- The freaking steering columns that GM used in much of their line of sedan and coupes throughout the middle of the last decade. Have had it lubed four times, and replaced once. GM covered it out of warranty as they know they are a problem, but also because they replaced it without asking us first. LOL.
- Now have very slight oil leak from timing chain cover. Yes.. the 3.5 has a timing chain... This isn't a big deal yet.
The car gets great HWY mileage even with the V6, repetitive fill ups on long trips have topped at 37 MPG. The car is the perfect size for what my wife likes to drive. That year, it was one of the safest cars on the road in it's class. We now have just over 60K on it.
Needless to say, I know it is an economy sedan, so my expectations weren't that stellar. There has been enough annoyances however, that I'm skipping even considering GM for our next two vehicles. Ford is probably going to get our next purchase this year to replace my truck, and probably the Malibu eventually.
I've owned used Pontiacs and Chevy, and some were great cars, and some weren't. Those were 1978, 1983, 1986. For a 2005, I thought the Malibu would be of far better quality than any other GM product I had owned. The amount of nagging little issues for a 2005 car however is ridiculous.