Engine low power going up hill?

I'm having the same issue, did you ever verify the problem?

I took three videos, or tried to anyways. First two with windows up. Third one with them down. Pretty hard to hear it over the engine in the video. When I tried to capture the noise it was more sustained this time. Like sssssss, usually it's more like a ts-ts-ts-ts. Also I didn't realize this page was for the 4 cylinder. Mine's the 2.5 v6 4x4. Any help is appreciated.

I'm starting to think fan clutch. Randomly caught this video: https://youtu.be/BR-uLMTaOXY
My fan free spins pretty easy. But I'd think it would make the noise while parked and revving too, but it sounds fine. I don't have a level area to lift the car and run it up to speed. I'll probably end up taking it to a mechanic. Took another video with windows down because it's doing it more under less load now. You can hear towards the end when it kicks into cruising gear it goes away. Didn't catch it in this video, but I swear I can hear belt squeal from time to time too. Still nothing solid though. I'll bring any results I get.

Solved! It was a problem of my own design. Last year I put new catalytic converters on. I rushed the job towards the end because I was tired of rolling around in the mud and rain. Anyway, the doughnut gasket between the Y pipe and the straight catalytic converter with the spring bolts has worked itself loose. The reason it wasn't making the noise while parked is because there was no road vibration, not from lack of transmission engagement. The reason it felt gutless up hill is because the tracker is generally gutless uphill and the noise was "scaring" my foot off the gas. I figured it out when I heard the noise after hitting a pot hole at lower rpms and speed. The noise "bounced". It then occurred to me. The fluttering noise was the spring bolts trying to hold the pipes together. In the picture you can see the doughnut gasket is crooked. I'm guessing the belt noise I thought I'd heard was whistling. So this problem was specifically mine, but I figured I'd write it up anyways. Maybe someone can learn from my mistake.

Final Verdict.
Must have been chunks of old catalytic converter in the Y pipe. (Or I have bigger issues) But they dislodged and ended up clogging the lower catalytic converter. That caused back pressure that blew out the donut joint gasket thingy, and robbed all my power. So there's my lesson; When you replace the upper catalytic converters, check all your lower pipes too. I really should have just replaced all three catalytic converters on the first go.