I got my hands on an OEM service manual and went through the test procedures. Pressures are 270 and 22 in TA, 245 and 21 in middle position, and 270 and 22 in DD. Steering to stops is 40 and 0. I may not have been clear in first post- tractor will pull and move in both TA and DD, it just won’t take off until you give it some throttle. Tractor responds when shifting from DD to TA. I’ve put in several TA’s, just none showing these symptoms.