I have a 2006 with the 5.9L. I was changing the oil last night and noticed the front of the oil pan was wet. apon further inspection the area behind the balancer was wet also. My first thought is front crank seal. Is this a common issue with the Cummins engine? If it is the crank seal how hard of a job is that? Is there anything else that could be leaking up there? The pan is pretty uniformly wet across the front so the leak does not look like it is from one side or the other. Any thoughts?

 

Mine had the same issue. Its the front crank seal that is causing this. I just tighten down all the bolts on the oil pan (be careful not to over tighten and break the bolts) and cleaned off the oil pan with a de-greaser, no more leaks. If its really bad where oil is dripping out you will have to get it replaced. Pretty time consuming so labor will empty the wallet. My dads truck was had a wet oil pan from the front too. I'm sure its a common thing for all used Cummins engines.

Cheers.

 

Are you positive it is oil, the last time my coolant hose coupling near the Turbo leaked I swore it was oil from the crank seal.

 

Now you got me second guessing what i saw. I will look again tonight.

 

Same experience for me, wet oil pan in front, tightened all the pan bolts down, and it's been dry ever since..

 

Oil can leak from crank seal or from pan gasket. If it stopped after tightened pan bolts then the crank seal is good. It was leaking from the gasket.