Well, it was time to change the oil yesterday, 04 Lariat 5.4 with about 118,000 kms on the clock (about 70k miles). The oil drained as normal, dark coloured after 4800 kms since the last oil change. The thing that concerned me was the froth under the oil filler cap. It wasn't a ton of it, but there was some. I have never looked there before so I don't know if it was there the last time I changed the oil.
The coolant level is fine and like I said the oil was dark, no white stuff in it at all. The truck is driven by my wife everyday and has time to get up to running temperature daily as well, but the drive is probably only about 15 kms, some are much longer.

Do I have a problem? I think I am going to do a compresson test on the engine to see if there is something obvious, but I wonder if anyone else has had this?

 

Never mind, I did a search and it looks like the wife needs to drive an extra time around the block after dropping the kids off at school to get some heat in the engine.

 

Yep, and I would suggest doing that just before you change the oil. Drive a decent distance, 10-12 miles or more, then let it sit for half an hour to cool. Then do the change.

 

That is exactly what I did.