Yes, it can building enough pressure. I learned that from my school. It is blowby which is caused by worn ring on the piston. The worn ring allow the air/fuel leaking through the seals and create the pressure in the area where the crankshaft is. Then, it will blow out the dipstick and cover the engine with oil....or blow up the engine...
Air ventilation
"During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by". [6] If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust. [7] To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the PCV valve into the intake manifold. The intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going.
If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced. [6]
Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick[8], or out the PCV valve."
http://en.wikipedia.org/wiki/Blowby
Hey viperpoweredram...you should check your air filter to see if there is any oil on it. Check the pcv valve too. Does our truck have the pcv valve? :dontknow: