My truck runs fine but after pulling an 8k trailer on a 3k mile road trip I seem to have alot less power at extreme setting. I heave replaced the fuel filters, cleaned air filter, boost is 26-28 with no excessive smoking, egt's seem normal and I am at a loss. Any ideas on where my power went?

Boost leak would be a first guess. Low power is also a symptom of failing injectors also. My injectors are going bad and I noticed that the truck is boosting more just to run unloaded going 75mph on the freeway. What's yours doing?

I havent really noticed any difference at 75 but I do seem to be using more diesel fuel. I dont think I have a boost leak because my boost pressures are the same. I wil pressure check charge air system though and visually look for any small holes or cracks. My injectors do have 100,000 mi on them so maybe that is the problem :(