Any mechanic worth a crap will replace the oil cooler along with your EGR delete. What that means is, ask him what he plans on doing with it and if he says "nothing" or "I'm gonna clean it", thank him for his time, get in your truck and find a new mechanic.
What caused your EGR to take a crap was that it was plugged on the coolant side of it. It is certain that if your EGR was plugged, so is your oil cooler (coolant passes thru the oil cooler first then the EGR cooler), the oil cooler will be next to go and it is not easy to clean up the coolant passages to remove the oil that will leak into them.
There are a couple of ways to watch your EOT/ECT. You could get something like the Edge Insight or get a set of manual gauges. You might want to add an oil pressure gauge. If you tow you may want to watch trans temps and Exhaust Gas Temps (EGT). A fuel pressure gauge would not be a bad idea, since under 45psi and your going to start replacing injectors. The stock spring that regulates that pressure can allow that pressure to fall to that level.
The Insight can watch EOT, ECT, Trans Temp and if you buy the extra probe the EGT. There are alot of other parameters it can watch, but not the other ones mentioned. The Insight can also read and clear engine diagnostic codes.
You will need a manual fuel pressure gauge, should have a manual oil pressure gauge and just for giggles most run a boost gauge.
As far as cost of replacement of the oil cooler, it won't be much more since everything is out of the way to replace it when doing an EGR delete.
ECT when up to operating temp will be around/close to 190, EOT should not vary from whatever that number is by more than 15*. If it does your oil cooler is plugged up and needs service now.
Fuel pressure should be around 55psi @ idle (or thereabout) and no less than 45 at WOT. Ford has an updated spring kit (about 50 bucks) to raise this to around 60-70 psi @ idle (part number 3C3Z-9T517-AG) should you find that pressure on the low side.
Oil pressure will vary from 30 psi to somewhere very close to/over 100psi. I get 100psi when it is cold, 75 psi when it is warm and I am @ WOT and around 30 psi @ warm idle.
Trans temp will vary depending on what your towing, it shouldn't get too much more than 180*. Mine hasn't gone over 170*F when towing my enclosed 8X16 trailer loaded up.
EGT should not go above 1300* for very long.
Boost is one of those "fun to watch" type of gauge and a truck in stock form doesn't really need it.
Last edited by NYC F-350; 02-15-2011 at 06:42 AM.
Reason: Typo, it now reads correct (it said edge would watch eot and eot, duh)