you have a blown head gasket . you have ran the car way to hot , and now you have water mixed in with the oil....
I have a 2004 and there isn't a fuel filler cap release.
headgasket blown.also sometimes a creamy residue on oil filler cap which is a tel tel sign
The Head Gasket is probably on its way out. Check the oil filler cap to see if its gone all creamy
Condensation of moisture mixed with the oil film inside the cap. If oil in oil pan is not "milky" you are ok.
Oil filler cap cover the hole in the engine where engine oil is added
An oil filler cap is a metal that covers the hole where the oil is poured.
Filler cap for 1400 jcb backhoe
if it is a creamy color coming from a radiator look in the oil by looking at the inside bottom of the cap,if it is creamy too,then you have a blown head gasket. that creamy color is water and oil mixed oil mixed in with the water, you got a blown gasket
if the build up you are talking of is sludge, it could by caused by coolant mixing with the oil. The intake's are prone to leak on the Chevy line and it will let the coolant leak to the inside as well as to the outside. Look in the oil filler cap for a white milky looking goo, if it is present you have problems.
Open filler cap, add oil, replace filler cap...
there is no filler cap. pull the tranny dipstick and use a funnel.
Check inside the oil filler cap for a brown creamy residue, this is an indication that there is moisture getting in through the head gasket.