Gearing question

I had the car on a chassis dyno about 2 years ago. Tell me what you think about this. The pull started at 2400rpm and eneded at 6200rpm in 3rd gear. It had a level 300hp all the way thru that range. It never varied more than 2 or 3hp. That tells me the trans or converter has issues, but I don't know whether to believe the results or not. I had dismissed them as bogus until now. You don't notice it when driving, but maybe???