I need a scan tool that can access GM transmission and transfer case data. I retired from the transmission rebuilding trade. i am used to Snap on Vantage, OTC Genisys or GM Tech 2 for what i needed. I bought a Maxi Scan 501 to be sure a more expensive scan tool was worth investing in. Now i want to buy a Maxi Diag 802 or Maxi Diag Elite. I will only be using it a few times a year, so i am trying to go to the least expensive model that will get the job done... It must be able to access data nd code information on Transmission and transfer cases. i will need to be able to watch input/output speed sensors and adjust EPC solenoids, turn on/off shift solenoids. Anybody's input will be helpful on which diagnostic tool will fit the bill