I have an 04 FX4 Screw with 58,000 miles on it. Ive recently noticed what feels like the transmission skipping or shuddering while going 45- 55 mph. It only does it while driving at that speed. If I'm slightly accelerating say upto 65 i cant feel it.

What do I need to do to fix this?

Thanks
Race

 

Are you sure it's not an engine misfire?

When was the last time you changed the tranny fluid?

 

I'm pretty sure its in the transmission. Its a slight tugging or jerky motion and it only happens if I'm driving a steady 45- 52. It doesn't do it if I'm accelerating or at any other speed. I haven't changed the transmission fluid yet?

 

I've had mine do that to me every once in awhile. It almost acts like it's hesitating or is in between gears, and when it does drop down a gear it jerks into it.

Someone posted one time that it's a PCM issue, that in that speed/power band the computer gets confused and doesn't know whether to go into OD or stay in the current gear, etc. If I remember correctly there's a dealer fix to where they flash the PCM with the update, but I haven't done it and can't remember which post I read it in. You might try searching for it as it was about a month ago now that I think about it.

 

At 58k you need to go get the tranny fluid changed. I'd recommend a place that has a fluid exchange machine so you can get it ALL out, unlike with a simple pan drop. There's no drain plug on the torque converter.

Those are still possibly symptoms of a low grade misfire, but go get the tranny serviced first.