Hello again i have a 1997 ford f150 4.6l V8 with a salvaged 2001 ford engine with an automatic transmission but thats not the problem the problem is when ever i put it into drive i have to acelerate it almost to 2000 Rpm! reverse is fine but 1st and 2nd also engage at 2000 rpm is my entire transmission bad or do i need to replace some clutch
part? or is my fluid to thin because it needed fluid and when it poured it in it almost poured like water.

 

Start by checking the fluid level, car hot, idling, and park and see where the fluid is. If it's not on the dipstick, add 2 quarts and recheck it. Then see how it engages.
If the level is ok and it still has this problem, then it doesn't sound good. More info (like which trans it is) would be helpful.

 

Signs of Transmission Trouble