I have researched this topic to DEATH. There have been a lot of posts about issues similar to the ones I am having, but I cannot seem to find a solid answer as to why they are occuring. I have a 2005 F150 crew cab with 80,000 miles on it. Lately I have noticed that when under a hard acceleration between 2500 to 3700 rpms the truck seems to not want to pull as hard as it should be. I feel as if the rpms are rising slowly but the truck is not moving as it should. Cruising around town in the lower rpm range you never notice anything. I do however get a hard shift,clunk,hesitation from the truck as well. I recently dropped the pan and changed the tranny filter. I was the first one to have it off I believe. The oil doesnt appear to be burned or discolored. I have read a lot about the Torque Converter causing strange problems... I just need to know what direction I should go in. Whether that involves dropping the transmission and having it gone through...or something HOPEFULLY slightly less expensive. I would appreciate any input from anyone. Thanks!

Michael

 

Does it for instance:

Clunk or jerk after hard acceleration? I mean when it jumps up a gear ... Say you nailed it in 2nd and let off .. Will if bump up a gear?

 

If I nailed it in second it and let off, I do believe there may be a slight clunk noise. I really notice a problem at 3000 rpms and 40-50 the truck does not pull like it should. And sometimes when I am crusing at 50 and I hammer the throttle, it seems like it should kick up into the passing gear, but it doesnt. Just wants to slowly climb from whatever gear it is in.

 

Torque Converter possibly????

 

I had the same problem with my 2005 F150. It was TQ converter lock up from what I could gather. I used Dr.Tranny Instant Shutter Fix and the problem went away. It's cheap and easy to do, so it's worth a shot.

http://www.lubegard.com/~/C-230/Dr.+...nt+Shudder+Fix