Chevrolet Repair: I may have blown it...literally, chevy silverado, dipstick tube

Question
I recently purchased a 1986 Chevy Silverado 1/2 ton pickup
with a 6.2 litre diesel engine, auto trans, 2WD, 142k miles.

The vehicle was running great, until I stupidly loaded the
box with furniture and hooked up a 6X12 trailer with more
furniture for a 200 mile trip.

Everything was going fine for about 100 miles at about
60mph.  All of a sudden, a big cloud of white smoke came
out so I pulled over to check things out.  I thought for sure I
had blown the engine. There was fluid which appeared to be oil
sprayed all over underneath the truck.  After letting it cool down, I
disconnected the trailer and checked the oil which was dirt
black and was actuall showing over full ( I know it was not) I
started it up and  drove to the next town about 8 miles
away.  I changed the oil and filter and started out again
(without the trailer)  I stopped about 50 miles down the
road and checked the oil again, and once again, it was dirt
black.  I made it to my destination okay, but I fear that I
pushed it too hard and caused permanent damage.  How
can I tell what the problem is?

Thanks

Answer
Hi Dan,
For one thing, those diesels turn the oil black pretty quickly, so don't let just that color scare you too bad.
If it was overfull, or the transmission squirted some fluid out the dipstick tube, it could have caused the smoke. See if it is red fluid or engine oil.
That engine will take a lot of abuse, so don't give up on it yet.
Look in the area of the fuel pump, right front corner of the engine, and see if maybe it is where the leak is. If the pump is bad, you can fill the crankcase with diesel fuel, which washes more black into the oil, and thins it down, also.
Van