[tomlin5]

have bad backpressure causing oil to blow into breather.have good vacuum to pcv valve.any ideas? am running a 300 I6cyl.

 

[miesk5]

Did you pull the PCV valve & check it?
If it's ok, other reasons here:
http://www.womanmotorist.com/index.php/news/main/1944/event=view

Do a compression & cylinder leak-down test.