I got my exhaust manifold replaced 'bout 2.5K ago, about a couple of days after that it started to blow white smoke/steam on hot humid days. A mechanic buddy told me that it is probably a bad "o ring". Now I am spewing a little oil out the tail pipe (about a quart every 500 miles). I had the head gasket replaced 3k ago and I'm not burning oil/coolant and not exceeding summer time engine temps.

 

Losing a quart of oil every 500 miles is not a "little". Check your PCV system and replace the PCV valve and hoses if necessary. If that doesn't help, get your compression tested.

 

It seems like I have been losing about that much oil also. I replaced th pcv valve when I rebuilt my topend. I guess I need to do a compression test also. It hasn't been smoking or leaking oil and its been running nice and cool also...damn 3vze. I need to start saving for a 5vze now lol