Re: Downshifting the E4OD or how to grind your teeth in a big rig!
My '94 FS Bronco 351w E4OD 3.55 diff, 31inch tires, sure doesn't act like that. It's fine, no complaint. The E4OD is controlled by the EEC processor, and uses a lot of the same sensor inputs for running the engine, as it does for shifting the trans. To my knowledge, there is nothing to adjust. Since you can force a 4-3 downshift by using the switch (the EEC reads the switch), that seems to say the trans is OK there. How does the engine itself run, OK?
There is one sensor (trans oil temp) that at least my '94 has, that is used by the EEC only for trans control.
By chance, do you have big tires on it, with the original diff. ratio's?