I have a 2004 F150 FX4 3v 5.4L with auto transmission.
After numerous small problems in less than 5000 miles, now I have a new problem.
We had just put 5000+ miles on it pulling 5th wheel trailer. It was loaded and under a heavy load for all of it.
Now I have "Oil" in the Coolant reservoir. Not just a few drops but alot. Coolant is nearly black. It is Oil not transmission fluid.
Please note: NO water shows in the oil.
Pulled a few of the plugs and NO water or oil on the plugs either.
Any ideas of where to start?