When I am going 40-50 mph and RPM is around 1500 my truck feels like it is missing or jumping. I can't tell what it is. When I am accelerating there is no problem but when I back off the gas to maintain 40-50 MPH the tranny acts like it doesn't know what to do. does anyone know what is going on? Its a 2003 scab 4x4 with 4.6

 

That sounds more like a low grade misfire than a tranny issue. I'd start thinking spark plugs and cops.

 

Ok I hope that is what it is. What if it only does it when its at40-50 mph and 1500 RPM

 

Did you check the fluid level? Has it (oil) been replaced at all? How many miles?

 

Could it be the torque converter locking, unlocking? Try turning off overdrive and see if it still does it.

 

I bought it with 60,200 miles and I have only put 600 miles on it. I have checked the oil and it is fine.

 

When I bought it I took it in the same day to have them look at the tranny b/c it sometime would shift hard out of o/d. The service manager said that the F150's in that year did that and it was normal but I had them check the fluid and drive it but they said that it was fine.

 

Check the mass air flow sensor to see if it needs a cleaning. The MAF directly 'talks" to the PCM (powertrain control module) and the ECM.

 

i had a 99 5.4 do the same thing to me, threw P401, replaced the EGR and it seemed to fix it, took a while for the code to throw, maybe 2 weeks

 

I will try the EGR b/c it has not thrown a code either so maybe thats it