I did an egr delete, and oil cooler about 4 months ago. I have been slowly loosing coolant since then. I assumed it was a headgasket and was going to drive till it blew but last week I had another injector die. I parked the truck and after 2 days had a pond of coolant in my driveway. There is coolant in the valley and it is leaking down the pass side of the truck. It never leaked under pressure until I drove it to my shop tuesday. I can not find the leak. Where is coolant present that I would have disturbed. I did replace all of the o-rings on the cooler and torqued every bolt to factory specs. It does not look wet there. Isn't there a large oring under the manifold by the front cover?