Oil in the valley
 

I have a 99, F350, 7.4 Turbo Diesel. I am getting an accumulation of engine oil in the valley just slightly forward of the turbo. It is about 3/4 of a coffee cup every 1000 miles or so. It is enough that it is a concern.

Are there any typical "look here first" place I should check to determine the source?
The truck has 166K on it and runs well other wise.
Thank you!
Eric

I have a 1999 e350 7.3. I had oil on top of the intake manifold also. I replaced the two rubber "O" rings under the turbo. If I remember correctly they're above the exhaust back pressure manifold, it's been awhile since I replaced them. I bought the "O" rings from a Ford dealer.

If the oil is more forward in the valley and puddled under the the fuel/water separator could be the HPOP (high pressure oil pump)

If so, look for HPOP high pressure line/s for the orings leaking or the brass plug underneath (the white connector in the image) . A common leak there as well as the lines. Since oil doesn't run up hill, if its wet towards the front and under the HPOP chances are its not a pedestal leak..

df and Hay,
Thank you. The oil is more to the rear almost right under the turbo. I'll try looking more closely. Thanks for the leads!
Best wishes,
Eric

Oil is puddling in the valley but about 10" to the rear of the pump. I am thinking the turbo oil supply line(s)? is/are leaking. Any advice on how to address this?
Thank you!
Eric