I have a 2004.5 Cummins 5.9 it had 74K mi when I purchased it, it now has 85K mi. i am getting a strong oil smell. I have not seen oil on the garage floor or added any oil between changes, I am not seeing any smoke or feeling pressure when the oil cap is off, there was a very small amount on the slobber tube. The truck is in great shape and doesen't show signs of rough treatment, looks new and very clean and tight. anyone have any ideas on where to start on finding a solution.

 

Are you in a enclosed area? What kind of oil are you using? Is it a engine oil smell or maybe a diff oil? Engine oil really doesn't smell BUT gear oil really smells if you over filled the diff that may be it!

 

No, it is when I am driving it and stop or slow down,I switched from Rotella to Valvoline premium blue. It may be diff oil I am trying to find out. Really like the truck, has tons of power. Thanks, the smell is really strong it could be the diff. oil

 

Sounds like you have a slight oil leak thats gettin on the exhaust and burnin, could be as simple as the valve cover gasket. Or it's the turbo

 

Or worse, got a valve guide or seat. Only way of telling is have all 6 cylinders leak tested.

 

no leaks that I can find, looked in under hood and underneath the truck, no oil on floor. Had it to two different shops, still no answers.

 

mine smells like engine oil if you fill it up high on the safe line if you only go half way up the safe on the dipstick you don't notice it?