I have a 2001 F-150 SuperCab w/ 158k (plus probably a few more due to the intermittent odometer) which I purchased a couple months ago.

It's been a great truck and out side of an EGR valve hasn't given me any trouble. My daughter was coming home from college tonight and the truck was fine on the interstate, but when she got off and went to accelerate at the light the truck would be fine up until about 30 mph then the engine would rev, but no forward momentum.

She nursed it home and I took it out and experienced the same phenomenon. Once it gets back under about 30 mph it drives fine. My first thought is that something in the transmission has gone south, but it always seems to be at about 30 mph and the transmission doesn't shift rough prior to that speed.

Any ideas?

Thanks in advance!

 

i would think that would be the tranny. my work van did that to me but at 25. couldn't get it any higher. but we swapped the fluid and it worked fine for a couple months and then quit again. ended up replacing the tranny

 

I am assuming this is a 4R70W with a 14 bolt pan and Transmission code U on the door sticker?

If so, It sounds like the Intermediate one way clutch failed OR the snap ring that holds the one way clutch on the drum came off.

If the transmission is shifting to second but will not shift to third, most likely the direct clutch for 3 rd gear has failed.

either way it's time for a rebuild.

 

Steve, what mjewell00 and mitymerc make a lot of sense. I would agree with them.