EGR Issues 870

[rtjohnson1982]

Hey guys, had the egr valve replaced on my 07 ISX about 4 months ago and the check engine came back on yesterday and computer is saying “EGR out of calibration”. Mechanic is telling me that there is no way to calibrate them and that it most likely failed and to try and warranty is out through Raney’s. Before doing so I just wanted to check and see if it could be anything else. Truck is running really rough. Thank you!!