I have a '99 Dodge Ram 1500 4x4 quad cab and it has been burning oil, but only on start up, when i drive there is no blue smoke at all. I have had it for 2 weeks and got the oil changed 1 1/2 weeks ago. They filled it to 3/4 in the safe zone, i looked at it today and it was on the add/safe line. Did it burn a lot of oil or is that not that much. Could this be the valve seals. On startup, it burns oil for a couple of seconds with a small puff, then sometimes a couple seconds but with a good size cloud, and then sometimes it does not burn any??? If it was the plenum gasket, would it burn oil as i drive (which it does not, only on startup)? If i had to get the vavle seals replaced, about how much would it cost or the plenum gasket???

Thanks