i have a 1999 ford f150 i just installed a used transmission everything was great, no problems. I left for my drive to work and noticed it started slipping and as i continued to drive it got worst looking in my rear veiw there was a lot of smoke so when i stopped to take a look the hose that carry the fluid had broke and all the fluid was drained, ok well i fixed hose put all the fluid back in and it started up when into all gears but as it gets up to 30 mph it feels as if someone is putting on the brakes dont know what this can be but as i slow it goes and as i speed up it does it again can someome tell me whats going on

 

If you ran it without fluid, it probably toasted the internals of the transmission.