Kasan Blake Shedd

I've recently swapped my automatic 94 3.0 with a 3.4. Used the ors wiring harness and all that good stuff lol. The truck started up the 3rd time I tried. Back it up on the trailer and took it to the exhaust shop. It will go into drive and move but it does not want to go anywhere over 10 mph. You can hit the throttle more and it does nothing. I did notice the speed input sensor wasn't hooked up and that it could be the problem. I haven't really seen anyone else have this problem on the forum but does the sensor actually control when it shifts or does it just control the speedometer.? Any input would be helpful. Just really don't know where to look to fix it

Smaay

since its an auto, speed sensor might have a lot to do with it.