At low speeds of 15-25mph, hard shifting occurs, at speeds above 45-50mph, the odometer drops from 3,000 rpms-2,000 rpms and the truck slows down, but if i press on the gas any, the rpms do not move and all i hear is the engine working harder but no reaction to the road, also when this happens, a rattle occurs. If i let off the gas and press again, the truck reacts with acceleration but does the same thing again.
What is wrong with my truck guys?? I took it to autozone and got it checked by the computer and no codes were shown but there is clearly something wrong.

Almost sounds like your catalytic converter(s) is clogged or getting clogged.

__________________
2001 Ranger XLT SuperCab 4dr Flareside 3.0 V6

alright, crawl under your truck and find your catalytic converters. Bawl your fist up and hit them, and see if they rattle. The problem you describe sounds like the catalytic converters are breaking up inside, and the loss of power would be described by the pieces blowing back into the pipe and clogging the pipe.

Sounds like what happened to me when I swapped my spark plug wires lol!

__________________
Old Ranger: http://i6.photobucket.com/albums/y243/8886060/Truck.jpg 306k Miles, and kickin'

Current Ranger: 1998 Ranger Splash, 134k Miles 2.5l 4banger

Thats so weird, I was just getting on here to ask about the SAME thing on my '01. All except the noise, which I haven't noticed. Other than that it sounds identical.

I guess I'll check the catalytic converters and keep an eye on this thread.

Could be the torque converter too...but the cat. converter would be cheaper and easier to check.