truck had been running great forever but was come home from work the other day and it started running ruff like it was running on 4 cylinders got it home and it was running fine ckd the alt to see if that may have been the problem was only putting out 12volts got a new one and installed it started truck and the problem came back put new fuel filter in and still donig it was thinking it may be the ipr or something else have ckd the valve cover gaskets all good but it does look like there is coolent in my oil on the heads i am lost on this one