Freshen up high mileage truck

[chevluv]

Hey guys! It has been great reading some of the information in this forum. I have learned a lot from you guys and you have helped me solve some of the minor issues I have encountered with my 2000 F250. Well, now the ol' 250, which has the 7.3, has 320,000 miles on it. I've been running a Superchip, usually in Tow Mode because I tow a trailer with a gross weight of 15,000 lbs on a regular basis. The transmission has been reworked twice. We all know that the transmission was never a strong point in these trucks. The motor still purrs like a cat, but she just doesn't have the power she once had. The only thing that has been done to the engine is the #1 injector went bad and had to be replaced at about 250,000 miles. There seems to be some slack in the rear end and there is an occasional pop in the front end with a quick acceleration or stop. I'm guessing that is bushings that are just worn out. My question is do you all suggest running her until she dies or should I go through the engine and freshen her up? What freshening suggestions do you all have. I wouldn't mind going back a little hotter since there are so many perfomance parts available on the market today. Just curious what you all have to say. I look forward to hearing from you!