I just put together a 97 C280 722.6 trans. Pre rebuild it was operating properly but developed an interment buzz sound like a screw driver against spinning gear teeth and had the light throttle torsional vibration associated with a dragging torque converter clutch.

Changed frictions , seals , K2 bushing , torque converter, Sonnax shift sleeve upgrade ( o ring sleeve ), spring in Control Valve Pressure Regulating Valve.

Post rebuild the trans is erattic and won't make it through the shift adaptation without triggering this code: 55 151 P0730 GEAR RECOGNITION REPEATEDLY NEGATIVE ( Got this code on the initial road test , zeroed out adaptations, shifts were less harsh but still erattic , still got code. )

Sometimes it will start out in 2nd when coming to a stop after a good 1-2 shift. The 2-3 shift seems to be OK, maybe 3-4, sometimes toggles up / down between 4-5 or maybe 3-4. Trans still shifts bumpy, will eventually default to 2nd but no check engine light until I cycle the key.

I pulled the valve body thinking that I flipped the spring / small valve in a shift sleeve, these are OK. All check balls are in the proper places. I have another valve body that I can pop in but I'd rather find the problem with this one.

Will also open the trans computer for a look for oil.

Any ideas ? Thanks