6.9L New guy.. Oil leak

[il_duramax]

Hey guys, 1st post. Nice forum

Ive been lurkin around and searching a bit. Just bought this truck, 84 F350 2wd Dually, 4 speed.

I did absolutley no research on this truck before buying it, Completely new to this engine so bare with me.

Guy sold me the truck for $400 dollars, Told me it had a real bad oil leak, and pointed to where it was leaking. Put about 3 gallons of oil in and itll last about 30 minutes.

Truck runs great, drives great so $400 for a work horse farm truck isnt bad.

So, Excuse my ignorance but on the driver side of the motor, on the bottom, under the exhaust manifold theres a tube that runs the length of the block, and goes into the block ( i think ) and where it goes in is where its leaking.

Can anyone tell me what that tube is? Common problem? Easy fix. cheap / expensive ?

[il_duramax]

I assume this is the oil cooler, correct me if im wrong