[sarujin]

Other things you could try.

Looking under your car for any wear or big scrapes. Check all the joints look in good condition (specially your CV joints). You could also check your electrical connections, and spray them with an electrical cleaner (stops them corroding).

Also you can do things like check your brake pads and discs, or drums for wear, and also clean them up a little (can help stop squealing).

Other then those suggestions I can't think of anything else, you're already checking most things.

Sarujin