Hey guys. I have been having a problem lately with my transmission. I have a 2003 Screw with the 5.4/ It has been slipping when I down shift from 4th to 3rd. It will jump about 500 RPM's and then go into gear. Its not shifting hard, just slipping. It mostly does it at highway speeds. I dont notice it as often while im driving around town. I had my transmission fluid flushed about 6000 miles ago. I checked the fluid and its at the right level and it looks fine and doesnt smell burned. I have about 75000 miles on the truck. Any ideas?

 

Anyone? Is the tranny going out? Its also not throwing any codes.

 

when it does this do you, let up on the gas? hold it steady? or give it more gas?

 

It happens when I give it gas to pass or if Im going up a hill and it downshifts.

 

Sounds like the converter is coming out of lockup before going down to 3rd gear.
You can check this by holding a steady speed, say 50, then slowly accelerate to 60, (but not hard enough for the RPM's to jump up like they do when passing)
Watch the tack and speedo, MPH & RPM's should clime at about the same rate.

Then do this again starting at 50 but now accelerate at a faster rate. (hard enough that the RPM's jump up the 500 or so RPM's but not hard enough that the trans down shifts to 3rd gear)
Watch the tack and speedo, RPM's should clime faster than speed. When you get to 60 mph try to hold speed at 60. The converter should go back into lockup and the RPM's will drop about the same 500 RPM's that it jumped.