How to wire up a 94-95 LT1 PCM so it controls a FWD 4T60-E transmission:



The LT1 PCM's outputs for the Pressure Control, 3-2 Downshift, and TCC PWM solenoids do NOT need to be hooked up to anything at all, so long as the trouble codes and diagnostics related to these circuits are disabled in the PCM's programming.

Keep in mind that the LT1 PCM is set up to work, from the factory, with a 40-tooth VSS sensor that spins at driveshaft speed.  The 4T60-E only has a 30-tooth reluctor ring mounted to the differential housing that spins at wheel speed.  So the signal the LT1 PCM will see from the 4T60-E is approx 25% that of what it is set up to see stock.  Be sure to make all the proper adjustments in the programming to compensate for this.

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