Hello every one I was hoping someone could shine some light on this problem for me. Ok van came from another shop they put 2 transmissions in it and rebuilt the last one and still could not get it to work (P2560 could not be fixed). Now the van is at my shop. Van would not move removed oil lines no fluid pressure. So replaced the transmission oil pump put the tranny back in, still no pressure, changed valve body, still no pressure. Removed a transmission from a good working sprinter and installed it in to this one P2560, P2561 van drives until it tries to switch to 2nd then goes in to limp mode. key off, key on, resets and the same thing again. Replaced 4 different egs modules same thing, replaced 3 shifters same thing, checked and rechecked all the wires going to the valve body all good. Removed oil lines from radiator put air through the radiator goes through easy. I got another sprinter with a good transmission but before I go replacing another tranny is there anything else I can check? replace the abs module? the wheels are 16s and normally a sprinter has 15 so try different wheels? also looks like the differential was replaced could that effect it? or maybe try a diffrent engine ecu? I am splitting atoms with this thing

sorry for the long write up. any thoughts at this point would be greatly appreciated Thanks
(p.s. i got 4 sprinters for parts so I have all the extra parts for it)