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4L60E wiring harness on driver side

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13K views 14 replies 5 participants last post by  davester3500  
Copied this from a post I read some time ago. I don't have the link anymore.


1995: Stand alone year! Will not interchange with any other year. This is a PWM transmission. An extra solenoid was added to the valve body to control the pulsed lock up strategy of the conerter clutch. It has a 12 pin case connector, extra wire in the transmission to computer harness and different computer to control the new PWM circuit. Has PWM cast in front pump. Front pump internal passages different to match new TCC strategy. 2 piece TCC control valve in valve body. Has holes in plate, marked in diagram below. 1st design 3-2 valve. 12 pin case connector. '94 computer won't recognise new TCC strategy., and will burn lock-up clutch and 3-4 clutches up. '96 computer isn't compatible with '96 3-2 control solenoid.

1996: The 3-2 downshift strategy was changed to an on /off arrangement. The TCC control solenoid was changed to a 20-31 OHM solenoid, from the previous 10-15 OHM solenoid. The 3-2 control valve was changed to the second design valve. The easiest way to identify the valve is, the second design valve will fall out as soon as the solenoid is removed. The first design has a plug and retaining clip. TCC solenoid remains 10-15 OHMs, which is the same as the '95 arrangement. Has PWM stamped cast in pump. pump is the same as '95. Will not interchange with '95 unless changing 3-2 solenoid, valvebody casting, and seperator plate. Has holes in plate marked in diagram. '94 or '95 computer will not accept the 20-31 OHM 3-2 solenoid and will throw an SES light and throw the transmission into limp mode. Some less knowledgeable builders will swap the solenoid so the computer will see the correct resistance, but the valve itself then causes downshift issues. If only the solenoid is changed, it will result in a 3-2 downshift cut loose. In other words...3-neutral-2 downshift. Speedo moved to passenger side of tail housing, but easily changed.

1997: Basically the same as '96

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