Originally Posted by Max Headroom
I would extend the tube to keep the vapors away from the cooling stack. You would not be adding any back pressure. Along that same thought, I would not add a catch bottle as this might cause back pressure.
Good point (actually critical) about not causing additional back pressure.
If just extending the crankcase breather, ONLY run the extension down hill. If a low point/drip look and you are in sub-freezing conditions, the water vapor can form an ice plug and cause excessive back pressure. Pretty easy to do. Just use a barb to barb fitting the same diameter as the OE hose ID. Get 5' or so of cheap, clear vinyl hose (sold by the foot at most hardware stores) and zip tie it in place. By the time the vapor gets to the bottom of the original hose it is cool enough that it won't harm the new hose. Been there done that for over 100k miles on our first coach.
I have no problem with a "catchment container", as long as the surface area of the exit/exhaust exceeds that of the hose ID. I successfully used a gatoraide bottle and used a hot punch to make holes around and just below the neck with a surface are of 1.5 times that of the hose ID. Extend the OE hose to about 2" off the bottom and zip tie it in place. Clean at oil changes. If you get more than a few ounces between changes, you need to determine the cause. By far the most common cause is over filling the crankcase with oil.