I have a 1998 E-250 5.4L Triton van. This year's oil test showed chemicals that indicate that antifreeze is leaking into the engine oil. I am going to change the oil and retest it in 2K miles to be sure, but I am looking for advice on where to go from there, if it tests positive. I have researched the upper intake which seems to have a problem with cracking and suspect that. Is there a good way to test it? The local dealer wants $80 to check, but said they may not find a small leak like I have. Also, If I replace the manifold myself, is one brand better than another? What other parts should I plan on replacing while its apart? Thanks for any answers that you may have.

 

Have you checked if the engine has an oil cooler where the oil filter is mounted?
Before you jump onto manifold systems , might pay to check oil cooler first.

 

Thanks Hanky,
That's why I'm here, I always want to hear from the people that know more than I do about these things. I just checked, and I do have a cooler on the oil filter base. Is there a method for testing them?

 

This is where it gets confusing.
Cooling system pressure generally is in the area of 15 lbs.
Oil system pressure can get as high as 50 lbs.
You would think that you should be getting oil in the coolant .
There are times things defy reason and logic and coolant gets into the oil.
I don't know of any way to confirm a defective cooler other than replacing it.
You can do a cooling system pressure test and see what the pressure test indicates.
How particular were the procedures for obtaining the oil sample?
Is there any possibility the contamination could have been introduced outside the engine?
I believe you are doing the correct thing by changing the oil and having the test redone. It pays to do all the checks before tearing into a job.