Has anyone experienced difficulty pulling the dipstick out of engine due to a vacuum being created? Once the dipstick is pulled out the first time and the vacuum is broken, it's much easier to pull out again (before the ngine is run). I think I read somewhere it may have something to do with crankcase ventilation/oil separator (I've changed the hoses that connect to the oil separstor - those ones that run across top of engine and degrade after about 40,000 miles).

Is it possible for a vacuum to be created in the crankcase and is this a problem/concern? Any possible diagnosis and fixes if so?

Thanks in advance for any comments.