My friends 1996 GMC Yukon with 110k has a MIL code of P1870 displayed. This is displayed when the trans gets hot as in normal driving. The Yukon has a 4L60E auto trans and a 5.7L V8. The trans then has a very harsh 1-2 shift. The MIL TSB says the control Valve Body is worn and allows TTC slippage. Solution is to replace the Valve Body with a revised VB with the upgraded TCC regulator and isolator valve IF the ATF is not burned or the Torque Converter is not blue, as in overheated.
My questions are: is anyone familiar with this trans problem? Is it better to buy a new VB or a reman. VB? Is this something a good shadetree mechanic can do in the drive way , it he has the proper tools? Any tips? We'll assume the ATF is not 'burned'.
My questions are: is anyone familiar with this trans problem? Is it better to buy a new VB or a reman. VB? Is this something a good shadetree mechanic can do in the drive way , it he has the proper tools? Any tips? We'll assume the ATF is not 'burned'.