Needing some help guys! 2004 f250 6.0 with 166k on the clock. Truck has been great the past 3 years or so. I'm the second owner and have only done routine maintenance up to this point. The last month or so I've had to replace the FICM, both batteries, and an alternator. I'm having an issue with what feels like weak upper rpm power (3200-redline). I'm running an SCT tuner with both Eric's extreme street and most recently Matt's SRL tune. Truck pulls hard at 75% throttle but full throttle feels weaker! Turbo making 28-30 lbs of boost, no puking (but not studded yet), ECT-EOT deltas run 4-8 degrees, no codes since the FICM was done. Checked my fuel pressure this week and found I have 40-45 psi at idle and 30 psi or so at WOT! This is with the blue spring for the regulator installed! I have no smoke at startup, a little injector stiction for the first 30 seconds or so, but it idles and runs smooth enough to drive immediately after startup cold (35* here this morning). I have some rev-x ordered to try and I'm replacing my fuel pump HFCM today. Just wondering if the weak fuel pump is robbing some power. Anything else I could check? Thanks guys!