I seem to have excessive blow by.

Currently I am going through 1qt of oil every 400 - 450 miles I notice it comming from my breather while sitting at a stop light after running 50mph or so after the truck is warm have not found any other leaks.

Does this sound like it could be the vac-pump or something worse?

 

Where is this breather located?

 

breather is located drivers side, about 3/4 of the way back on the block, about 1/2 way up the side.