I have a ford 3000 and yesterday it started slobbering out the exhaust stack. It has never done that before or anytime this year , and i check the engine oil and it was way over filled I drained out about 3 Gallons of oil/think diesel but it was not over filled with engine oil, I think it was diesel fuel, because the radiator antifreeze level was still full. I just change the oil today and tryed it out for about 1 hour, and it still is slobbering out the exhaust. What could be the problem?