My truck has been blowing some oil for a while (1 qt /3000 mi), but in the past few weeks (201,000 miles on the clock) it's been really bad- like a quart every 100 miles. Back in '07 I did the KDP thing and I thought that maybe we didn't seal things back up correctly. I did look under the truck and could see an oil drip between the vibration damper and the block. Two weeks ago we went back and put in a new front seal and gasket on the gear housing cover.

I thought everything would be cool but I just noticed oil on the tailgate of my truck again. I looked underneath and it appears that the oil is mostly on the driver's side.

I've heard that the vacuum pump can cause problems-- I did notice on Saturday that my ac vents went to defrost and wouldn't change to vent while in traffic. This only happened once though, and hasn't occurred again since then.

One other question- where is this blowby or vent tube that people have mentioned in other posts?

 

A vacuum leak will definitely cause excess blowby and if your vents have defaulted to defrost you definitely have a leak.
Blowby tube is the one below that starts by the fuel filter, passes behind the starter motor and ends about in the middle of the oil pan.

 

Thanks for the feedback Bill. Where did you find that engine diagram?

 

You'll find a wealth of Cummins info along with the diagram here http://dodgeram.org/support_pgs/diesel_ix.htm

For non Cummins parts of the Ram go here http://dodgeram.org/support_pgs/tech_index.htm