Re: e40d problems
It isn't shifting between fourth and fifth. It is a four speed transmission, not a five speed.
The other shift you think you are feeling is the torque converter locking and unlocking. It is likely that the torque converter is causing the problem. You can get the converter replaced for a big portion of the rebuild price.
I don't know how to fix this problem with out spending money.
Former Ford Automatic Transmission Engineer
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