With light throttle through the shift sequence when engine rpms are allowed to go to or remain in the 1,500 range I get a third gear shudder up to 1,800 rpms or so. If I maintain engine rpms at or above 2,000 I don't get the shudder. If I run manual shift through all the gears at or above 2,000 rpms I don't get 3rd gear shudder. It only happens in lower rpm range midway through 3rd up to approaching 3-4 shift. All other gears shift seamlessly.
Initially I had DTC's 43 & 44. I cleared those codes drove the car about four miles going through the gear sequence a number of times and experienced 3rd gear shudder a few times but the codes haven't come back yet. I also ran active tests on all of the solenoids and got audibles on all of them except the TCC solenoid. Should I get an audible on the TCC solenoid test? And what's causing the shudder? I'm seeing codes 43 & 44 diagnostics include verifying correct pressures. If they're good I need to remove the valve body and inspect the o-rings for possible leakage and the valve body for wear or damage. Other than that it would be a 3rd U/D issue requiring a rebuild of the 3rd U/D. Anyone want to take a stab at these symptoms and how to fix it or am I on the right track here?

 

Hi. Sounds like you're on right track.
TCC. Strange that it only happens in 3rd? NO shudder in 4th at light load/throttle?
Q: What reader / software are you using?
Jeff