I am getting code P0700 on my new to me Suburban and have noticed some erratic shift. I have tried resetting the module via the numerous way the internet suggests and I have added instant shudder fix to the fluid. The fluid is new as it was replaced less than 1000 miles ago via flush. Is the TCM something I can buy and replace myself? If so where is this thing located and what will it take to get to?

 

Hello for some reason people don't respond here I will ..The TCM is in engine compartment drivers side on the front of the inner fender well firewall side the the ecu will be facing the radiator as well . Yes you can change it but as with changing any module it needs to be programed/ flashed .that you can also DIY if equipped properly and buy a program yourself..