My 1996 Eddie Bauer Ford Bronco is acting weird. The transmission is shifting hard, the speedometer stoppped working and the overdrive light is flashing. I've already been told it's not the transmission and I've changed the VSS like 4 times. Any other ideas guys? I really don't want to spend a crazy amount of money. But if I have to I will.

 

The flashing O/D light is trying to tell you something...pull the codes.

Please define "the speedometer quit working". Is the odometer display blank?

Replacing the same part 4 times then expecting a different outcome is exactly why good troubleshooting is highly advised.

 

The O/D light flashing and hard shifting indicates your transmission is working in fail-safe mode. As you've been told, it doesn't mean your trans is bad. If your odometer isn't turning ON I think the cause of your problems is there, the VSS and PSOM (part of your dash clock set, including ODO) work together with some other sensors (letting those out for now) to send the transmission the signals it needs to operate, since it isn't receiving input from the PSOM it's acting up.

 

Could also be the wiring cable running to the transmission.

 

The problem isn't the transmission, not directly. Even if it feels like it's possessed by demons. 'Safe-mode' is the term. Blank odometer, non-functional speedo are additional clues. It may be part of the feedback (depending on year) to the tranny or the rear differential speed sensors, a failed PSM or, the one I got to experience, lost power to the PSM.

One of the nuttiest engineering stunts ever, IMeversoHO, is that the power for the PSM is supplied by a light amp circuit that runs all over the trucks. If you have a short in any of those various offshoots, the PSM loses power and you ... yeah... go into safe mode. Or it can be the chip, or ... or ... or.

Check your fuse block, if memory serves it is fuse #8 (?). Mine had that version of the failure. If that fuse is blown, you may be able to determine if it is the PSM or not by replacing the fuse (power off) and watching the odometer closely as you turn the switch ON. On mine, a replacement fuse lasted just long enough to let me see the odometer flash digits up before the fuse went.

That put me into sleuth mode following the various connections around. Mine was eventually found to be a condenser on the board on the module monitoring the air bag system, at least I think that's it. Blue one located under the dash, just to the right of the steering column? That was after chasing wires all over the rest of the vehicle.

Run some searches for 'hard shifting' and 'transmission safe-mode'. Don't panic. You'll need some patience for this one. Luck does not hurt.

 

This thread really makes me want to find a C6 tranny and ECM and swap out this E40D.....

 

On my almost 400k miles just once has the E4OD failed on me, and the thing even brought me home (I was 1 mile away when it happened), even with broken gears and all. Sometimes they can cause trouble, but it's a rare occurrence.