I have a 1990 F150 with a M5OD R2 transmission 2wd. 5.0 engine. I just swapped it out for a new transmission, another M5od R2. The driveshaft goes about half way in and doesn’t go any further. It actually seems as if it has bottomed out. I tried wiggling it it wont go any farther in. The driveshaft turns on without binding up. It really just seems like it is fully bottomed out. Any suggestions?

 

Better check everything, something has to be different somehow or another.