You need to run it long enough to drive the water out of the oil...ie get the oil over 212 degrees F. Usually that takes some highway running.

Yes, diesels get water in the oil from condensation but it is a much smaller amount of water.

Never change your oil, and save the EARTH and possibly your children's limbs or life!
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Thanks
240Joe

1980 240D Auto >300kmiles - never blown up!
1983 300D >150kmiles - also never blown up!
1987 300SDL >170kmiles- SOLD before I blew it up!

Certified ASS-HOLE (Automotive Secret Society - Head Of Logistics Engineering)