I have a 2004 Ford F150 4x4 automatic transmission truck. The truck goes forward but is really sluggish as if there is no power in forward gears. Reverse is fine. I got a trans fail light and the overdrive light was flashing too. I checked my tran fluid and it was low so I added some. It didn't fix the problem. It still has no power while driving. I couldn;t find any leaks to loose the fluid. Any idea as to what would be causing this?

 

You need to take it in to a technician that has a scanner that can read Ford transmission codes.