I just bought a 2010 F150 FX4. I am having issues with it under two conditions. When it shifts to 3rd gear, it seems to start running rough. Secondly, when I am at 50 mph and I goose it to pass, it falls flat. It will shift, but has minimal power.
I have taken to the local Auto Diagnostics place: They told me to have the Catalytic Converters replaced and have new spark plugs installed. After replacing the CC's and new plugs, same issue?
I took it to another local mechanic. He test drove it and said the transmission wasn't immediately downshifting when going 40-50 mph and doing a hard stop. He said it would pause for several seconds and then he would hear a loud clunk and it would shift into 1st gear.
I tested under the same conditions and it did the same thing. After doing a search, one of the possible causes was low on fluid. I took it to the local oil change place and they said it was over a quart low on Trans fluid. They topped it off.
After the fluid was topped off, it seemed to downshift as it should.
I took it to two transmission shops. They both said the transmission is good. One of the shops said there was a vacuum leak on one of the 4wd acutators. They suggested replacing the 4wd actuators to possibly fix a vacuum issue and consequently fix the performance issues.
Had the actuators replaced... still having issues.

Any mechanic that has looked at this truck in the past 3 weeks says there are no codes indicating any issues with the motor or transmission?

I was told that the issue could be the Transmission output speed senor?

HELP!!!!

 

Im real sorry you got bad advice from so many people and spent a fortune trying to fix it. Maybe you should have started at the Ford shop. If they fix something that doesnt fix the problem they are on the hook to make it right. At this point that is where I would go with it and have them fix it this time.
You have heard enough guesses already.

 

I took it to a Ford shop? I’m assuming you are talking about a Ford dealership service department? They couldn’t figure out the issue. In the process of overcharging me for new plugs, causing an exhaust leak, and replacing brake parts that were not needed, they told me they were backed up in there service department and I would have to reschedule at a later date to move forward!

 

Was the dealer able to tell you if the lead frame recall was done? Are you familiar with lead frame transmission issues?

 

I was told nothing about the lead frame recall. I was told by someone else that it could be the output speed sensor.

 

You should have called Ford district rep, that dealership is obligated to make it right if they charged for a repair that didnt fix the issue.

 

Thanks for the info! I am scheduled to take it back to them on September 11th to fix the exhaust leak that they caused! I will push the narrative with them!

 

Check the drive shaft if its the two piece unit.

Where the rubber connects it needs grease in there, the spindle could be worn or gunked up

 

Would that cause the performance issues that I originally posted?

 

Adding to the misery! I now have a damaged plug on cylinder 2 and a PO302 code.