E99 Transmission acting up, won't downshift etc

[Diesel1050]

Hope this is the right forum, haven't been on here for a while. Recently bought an e99 F-250 7.3. Truck has 233k on it, runs like a top. That being said, shifts from 1st to 2nd, and 2nd to 3rd are perfect, has tons of power and no hard shifts, 3rd to O/D however occasionally will shift hard, more so when the TS6 chip is on BUT still does it without the tuner. Not coming up with ANY codes, read with a snap-on solus, and autoenginuity. The O/D light DOES blink BUT that's due to the cluster wiring being messed up (Speedometer only works once in a while). When the Speedometer does work the O/D light shuts off. Replaced vss on rear diff. The big problem is, its shifts 1st, 2nd, 3rd fine but O/D damn near stalls it when it shifts. RPM's drop from 2500+ to 1200 and it barely speeds up until on a flat surface. Almost feels like it skips from 2nd to 4th. When it is in O/D even if you put the pedal to the floor, it doesn't always downshift. Any ideas?

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[DieselDC]

Bad cakes or broken springs or both.

As far as OD, your abs module or the wiring to it is bad. Speed is from abs module and blinking Od as well.


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