I have a 91 F150 w/ only 110,000 miles....... and it shifts hard - and very jerky- after highway driving. Like say right when I get off of the freeway and drive through town. What the heck is going on???

 

Do you ever do extensive city driving? I am wondering if maybe you have a warped clutch disk that heats up after a longer drive and then expands to cause a drag that prevents total disengagement. I had something like that and when it was shifting hard I found the drag not so bad that (from a standing start) if I held the clutch in for a few seconds before shifting it would shift easy.

Don't know if this helps, but may stimulate some other posts. Also, can try posting in the tranny forum.

"Drive a stick young man! There'll be plenty of time for automatics when you're old and unable."

 

>Do you ever do extensive city driving? I am wondering if
>maybe you have a warped clutch disk that heats up after a
>longer drive and then expands to cause a drag that prevents
>total disengagement. I had something like that and when it
>was shifting hard I found the drag not so bad that (from a
>standing start) if I held the clutch in for a few seconds
>before shifting it would shift easy.
>
>Don't know if this helps, but may stimulate some other
>posts. Also, can try posting in the tranny forum.
>
>"Drive a stick young man! There'll be plenty of time for
>automatics when you're old and unable."

Thanks for the reply, TAllPaul. Mine is an auto transmission, so I can't "hold the clutch in", and I agree that some kind of heat-up/warping is going on. Now... what is the fix. The entire tranny is new as of last fall. So why did the problem begin in the last few weeks? Warmer weather? Any tranny fluid issues possible? I checked and added a 1/2 quart of fluid as a precaution.

 

Ooh. Sorry, I should have figured the problem description was more auto tranny sounding. Juice box is as mysterious to me as grey matter. Could try fresh fluid (synthetic), but seems to be more than that. Wonder of cooling line is clogged, maybe need auxilary cooler installed. Can you get a temp gauge? Does is seem to run hot. Presumably off warranty or you would have gone back to the shop.

 

Maybe what it is, is that after the motor spends time at high rpm, it works up alot of line pressure in the transmission. When you get a shift kit, it increases the line pressure for harder shifts. Just a thought I had.

 

I'm not sure which transmission you have. If it is an E4OD you may want to consider the Manual lever position sensor. It is located on the driver's side of the trans. There is a TSB on this, although I don't know the number. The cause is water gaining access to this sensor. From what I understand once water gets in it this condition will occur regardless of the weather being wet or not. I'm not a mechanic, but this has happened to me. It may not be the root of your problem, but something to look at. Ford offers a replacement kit that has upgraded seals to help keeep the water out. I hope this helps.
judgeroy