MORE OF AN FYI:

2008 super duty f250 lariat powerstroke diesel.

I just had the truck in the local specialized independant Ford shop for a month for a coolant leak and then chasing around a coolant overflow pump issue with Ford techs.

I read about the radiator issues and the horror stories surrounding them - yes I was told by the dealership (2 locals) I am the "not under warranty" for a leaking radiator at 40k miles. I subsequently paid and had the radiator replaced at my local independant shop ( I think Ford has enough of my money) and then learned that the overflow pump was also bad so I had to pay for that as well. $1,600.

After getting the truck back, not two days later that old familar sqweelllll came back and people looked at me funny again at stop lights. As it turns out the overflow pump failed again. Then a few days later again - #3 !!! So this time my mechanic got on the horn again with ford and the diesel techs and they diagnosed, tested a few things and brain stormed for three weeks. A remote cooler (maybe the EGR) had an internal crack which the local machine shop fixed and this was thought to cause fluid from getting past the overflow pump and keeping it lubricated and in operating condition. In addition, the conversation came up on the termostats and how they can fail and cause radiators to go (plural for some owners). They were replaced.

My mechanic kept thinking despite what the techs were saying what is the coolant flow diagram and chart supposed to look like and how can any of this not get fluid through the overflow pump???? He finally got the flow diagram and looked to the EGR and the remote EGR cooler area.

PIN HOLE LEAK IN THE EGR COOLER LINE !!!

Wish me luck on getting this under warranty !!! FYI to those who may be having some issues similar to this and FYI to Ford who makes the truck.