transmission problem?
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Joined: Feb 2008
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transmission problem?
I have a 02 f250 4x4 with 5.4 and 4r100 tranny. The problem i have is that the transmission doesnt seem to downshift properly when braking. It seems to just coast like you put it in neutral. Also the torque converter unlocks whenever you leave off the gas when at highway speed and then locks back up when you get on the gas again. This is very annoying because it wont stay locked. It constantly is reving up everytime you give it gas before the converter locks. Could both problems be associated with a particular sensor? This seems to be an electrical problem but i dont know what sensor would control this?
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,734
Likes: 2,661
From: SE Florida
The torque converter is supposed to unlock whenever you lift off of the go pedal. That's the way the PCM is programmed, it's normal. It might not be what you want, but there's nothing wrong with it.
When you coast with OD enabled there is only engine braking in fourth gear. Once it downshifts out of overdrive there is no engine braking and the engine will go to idle speed. That's also the way the trans is supposed to work.
If you turn off the OD there will be engine braking in all three gears. If you move the shifter to 2 or 1 there should also be engine braking. Does it do that?
When you coast with OD enabled there is only engine braking in fourth gear. Once it downshifts out of overdrive there is no engine braking and the engine will go to idle speed. That's also the way the trans is supposed to work.
If you turn off the OD there will be engine braking in all three gears. If you move the shifter to 2 or 1 there should also be engine braking. Does it do that?
