F150 4.2L automatic transmission problem
 

hello!!! I have a 2002 f150 with the 4.2L in it. With and automatic 2wd transmission and I just recently had to put another transmission in it and after I had everything back together. I crunk it up Put it in drive and pulled out my drive way and thought everything was all good to go but when I got up to about 20 miles per hour and the transmission went to shift out of 2nd gear the engine started stahling out and the transmission starred shaking and shuttering and then it completely kills my engine unless I throw it into neutral. I can not figure out why it will not shift into OD and go on down the road. I can put it into 1st gear and go and throw it up in 2nd gear and it will shift into 2nd fine but then when it tries to shift up out of 2nd it starts shuttering and jumping and shuts my engine down and I have to stop and crank it back up. It will not crank back up if I am rolling down the road in neutral. Any help. Please. .??????