4L80 swap TCC relay setup

[truckfan2]

I am trying to find the tested proven way to make the TCC lockup with a 4l80 swap from a 4l70. I am running a TBSS E40 ecm and T42 TCM and have changed all the needed parameters in HPT like gear ratio, 3-2 solenoid disable etc...I am trying to figure out if you just use the soleniod control from the 4l60 to lock the TCC. I have heard the term fake relay to keep a code from popping up. Do you need to put a resistor on the TCC PWM output to hot to make the trans happy? I have also seen people use a relay powered by the PwM signal to make it a discrete signal. Anyone running it that can help out. I have the car on stands and would like to do this conversion wiring one time.




Jeff

[DSteck]

Don't disable the TCC solenoid, otherwise the TCC will not function properly with the 4L60E OS on a 4L80E.

[truckfan2]

Thanks for the diagram. Leaving the PWM output unloaded must be what gives the headaches for people judging by the looks of it.


Jeff

Don't disable the TCC solenoid, otherwise the TCC will not function properly with the 4L60E OS on a 4L80E.

[truckfan2]

Hey Dave,, can you take a look at my tune and see if you can tell why my trans only shifts from 1 to 2 to D then throws the P0787 code and wont downshift again until you clear the code. It wont shift into OD at all. It will start out in 3 if you dont clear the code. Also the 1-2 shift at very light throttle is horribly harsh.

Thanks


Jeff

[CSTune]

Jeff,

That code is for a shift solenoid. Could be a bad solenoid or wiring/connection problem somewhere.