Crankcase Ventilation Modification is a Bad Idea

Let’s talk about CCV (Crankcase Ventilation). It is stupid. In these trucks, in the stock configuration, your crankcase ventilation goes into the turbo and it takes the excess smoke through the turbo. You are going to get some oil past the ring; it is a diesel. A lot of guys out there in fantastic internet wisdom recommend this crankcase ventilation which is the absolute stupidest thing you can do.

First, you are venting this to the atmosphere which creates emissions, not that anybody seems to care about that. More than that, you never really relieve the crankcase pressure inside the engine. This creates a small vacuum. You are increasing the crankcase ventilation; it puts stress on the turbo seals. We have seen turbos come in here leaking on the exhaust side. When you take the crankcase ventilation off and put it back to stock, the leak stops.

I don’t know why that is; I just know that I have seen it over and over by taking the crankcase ventilation off you solve the problem. It is foolishness that you don’t need. The only reason why anybody does this is because oil ends up in the intercooler which is no big deal, it is designed to do it. Let the oil travel through the engine and then if it gets combusted, it gets combusted. This is a diesel engine, it will burn oil and it is happy doing it.

I strongly advise you not to do the crankcase ventilation, put it back stock and you will save the seals in your turbo charger. It will last a lot longer. These turbos are extremely resilient and can be repaired instead of being replaced most of the time, but once you blow the seals inside the turbo on the main shaft, you have to replace it. I am not a big fan of crankcase ventilation, I think it is foolishness. Leave it the stock way that works perfectly well. Yes, the engine will burn a little bit of oil, but I have not seen much if any oil consumption that mounted to anything because of the crankcase ventilation being left in the stock form. This is just some little kid out there on the internet creating a hype about something that is actually bad to do to your truck.

You can see the oil smoke coming out of the tailpipe. That is because it is pulling past the turbo. So either this guy needs to buy another turbo which he really doesn’t need or if he fixes the CCV and does it the correct way, all this smoke from the turbo will stop. You can see it smoking, unnecessary. Leave the crankcase ventilation system stock. ~Bill Hewitt