Ive just replaced every gasket on the upper engine....the rocker cover on the passenger side has tan coloured sludge on the top of it.....theres nothing on the rockers or in the oil...could this be condensation related to the pcv valve? Im at a loss for an explanation for the possable cause for this...Im not losing coolant and Ive drove about 100 miles since doing the motor work..I replaced the head gasket due to a failure on #5 cylinder...and the sludge is present on the other side..I cleaned the rocker covers on both sides so this is new...the other side is ok...Thanks in advance for your reply...

Was the head gasket failure putting coolant in the oil, and did you flush it out after repairs? Are you using cheap oil? PCV valve failure?

the head gasket caused coolant to enter #5 cylinder...there was no coolant in the oil (for sure) ..heres a list of all Ive done ...and I am using cheap oil at the moment..only because Im changing it in a few days because of the engine work I did
Head gasket ---compression test and was good
intake gasket
upper intake gasket
egr gasket
rocker cover gaskets
ehaust manifold gaskets
Y pipe gaskets
spark plugs
spark plug wires
distributer cap
rotor
pcv valve
oil change
catalytic converter
new o2 sensors
muffler
tailpipe


Also...I changed the oil right after I did the engine work...

I have heard cheapo oil will still do it. I have seen it back in the late 90's on a 305 and a 2.8 I put gaskets on. They both ran whatever was on sale. Are you making a bunch of short trips with it? In the right weather it could cause excessive moisture too.