Need help. 4t60hd to 4t65e hd swap

Been a long time since I've been on the forum. The ole 96 Riviera's been out of commission for about 3 years now. The other day I stumbled across a 97 in a junk yard. 126K miles on it and has a good wrench remanufactured transmission in it. Picked it up for some change and now I'm looking and the wiring harness for this thing and I'm so confused. Do I really have to pull the entire cars wiring harness or is there a short cut I can take? And BTW guys I plan on building my Buick all around now that I'm in a better financial situation. Hopefully I get some feed back on this cause I need the Buick back on the road in a week!

PCM, wire harness, yes. The 4T65E is MUCH more tunable than the 4T60, and has alot more logic in the PCM for it.

I already understand that, that's why I am doing it. What I am confused about is if I have to transfer the entire cars wiring to the other car. Like the plugs to the pcm instantly ties in with the rest of the cars wiring that goes to the back of car, doors, all threw the dash. Is there a way to just get the wiring from the transmission to the pcm out? Or do I really have to take the whole interior compleltly apart and every wire in the car?

Are you trying to put a 4T65E into your '96 replacing it's 4T60E? If so, you will need at minimum the wire harness and PCM. Fortunately once you start unplugging everything the whole harness isn't really all that hard to get out.

It's clearly stated 4t60HD to a 4t65ehd swap. I have read somewhere that there is only 5 or 6 extra wires and they can be ran seperatly and wired into the existing pcm plug with a 97 pcm. But everyone also keeps saying whole wiring harness. Which would require me to take the ENTIRE interior of the car apart basically cause the wiring runs EVERYWHERE. It isn't as simple as unplug an pull it out. Lol I'm trying to find a diagram or schematic of a 96 pcm plug and a 97 to see the differences. As far as the plug on the transmission it's self, the 96 has 7 wires and the 97 has 13.

the stronger 1997 transaxle will likely bolt onto your 1996 engine despite having a larger torque converter,
but there are pitfalls regarding if a 1996 PCM can control the 4t65e correctly.

you asked for the transaxle wire harness pinout, so this is page 7a-82 from a 1997 factory service manual:

https://s279.photobucket.com/user/Lmckinley99/media/riviera_1997_transaxle_wire_connector_1.jpeg.html?sort=3&o=2

it would be good to carefully compare this with the same page from a 1996 Riv factory manual.

what makes me most nervous is controlling the 1997's 4t65e torque converter, which is different than the 1996 4t60 torque converter.
one solution might be to install the 1997 PCM (that matches the 1997 transaxle) into your 1996 Riv.
......................

Here is a 4t65e description by Triple Edge Performance  (it may not be “gospel”, but it sounds about right):

The 4T65-E transaxle is a fully automatic and electronically controlled unit.  Shifts are all controlled by the PCM using two shift solenoids, line pressure is also fully electronic and controlled by a Pressure Control Solenoid,  which is commanded by the PCM.  This transaxle also employs the use of a Torque Converter Clutch, or TCC that is used to further enhance gas mileage and keep engine rpms lower.  

The TCC style in this trans is a PWM type, which stands for Pulse Width Modulation.  This style PWM TCC system was developed to allow for a smooth engagement of lockup and allows constant slippage of the TCC and can apply in 2nd through 4th gears.   The constant slippage is tolerable to the converter because of a special TCC lining developed especially for this purpose that is called a "Woven" lining.  An ordinary TCC clutch would burn up and shudder violently if used in this type of system.
........................

the question is, which type torque converter is your 1996 PCM designed to control ?
if you get this wrong, it could require removing the (newer) 1997 transaxle to correct a malfunctioning torque converter.

what follows is a link that explains the topic of how pulse wave modulated lockup works in similar torque converters:
https://www.transtar1.com/TranstarIndustries/media/Transtar1/technical/bulletins/TLT-TC-035.pdf

another page from the 1997 factory service manual follows:
https://s279.photobucket.com/user/Lmckinley99/media/riviera_1997_4t65e_wire_diagram_cell39.jpeg.html?sort=3&o=0

in the center of this image, the solenoid for the torque converter's pulse-wave lockup control can be seen.  it is directly driven by the PCM.  
again, the question is this:
will the 1996 PCM correctly control that solenoid?

finally, page 7a-83 shows the location of various electric solenoids on the 1997 valve body, all of which are
controlled by the PCM :
https://s279.photobucket.com/user/Lmckinley99/media/riviera_1997_4t65e_vbody_TCC_PWM_solenoid.jpeg.html?sort=3&o=1

consider the usefulness of getting your hands on a factory service manual for your car and also a copy of the factory service manual for the 1997 Riv.

it would also be good to have a long talk with a sharp transmission builder who understands the electric/electronic control of these transaxles.

I have the 97 pcm guys, I have the whole 97 car. I'm not controlling the 97 4t65ehd with the 96 pcm. I'm swapping the whole tranny, and pcm. I'm trying to figure out the wiring. I found a diagram on the 97 pcm plug. Now I need to find a 96 diagram and compare to see where the extra wires are. All I ask is that you all read my post and question carefully and not give me answers that is irrelevant. I stated that I have the 97 pcm, I stated that I have the 4t65ehd. What I asked is how to run the extra wiring. Not if my 96 pcm will control the new tranny, or if the 97 pcm is better, or if the new tranny will bolt up. I simply asked for the wiring advice.

crstump wrote:

I have the 97 pcm guys, I have the whole 97 car. I'm not controlling the 97 4t65ehd with the 96 pcm. I'm swapping the whole tranny, and pcm. I'm trying to figure out the wiring. I found a diagram on the 97 pcm plug. Now I need to find a 96 diagram and compare to see where the extra wires are. All I ask is that you all read my post and question carefully and not give me answers that is irrelevant. I stated that I have the 97 pcm, I stated that I have the 4t65ehd. What I asked is how to run the extra wiring. Not if my 96 pcm will control the new tranny, or if the 97 pcm is better, or if the new tranny will bolt up. I simply asked for the wiring advice.

I think Lance McKinley's answer was pretty good - although it involves tearing into those manuals.

Albertj

Does anyone have or can find a diagram or schematic whatever it's called on the 96 pcm plugs? That shows color of wires and what they run to. It would be nice to have the transmissions plug diagram too. There's gotta be one out there since I've found one for the 97. I've read there's only 5 extra wires but on mine the 97 plug has 7 more wires than the 96. Really wish someone would tune in on this that's done it before, I've tried messaging them but I'm not getting to them.

Here's the '96 4T60 connector on the ENGINE SIDE. The wires change color as they go into the trans.



Connector Part Information
12126467
7-way Metri-Pack 150 Series
Black
Pin
Wire Color
Circuit No.
Function
A
0.35
LT GRN
1222
1-2 SS Valve Control
B
0.35
YEL/BLK
1223
2-3 SS Valve Control
C
0.35
BRN
418
TCC PWM Sol. Valve Control
D
0.35
TAN/BLK
422
TCC Sol. Valve Control
E
0.35
BRN
241
Ignition Positive Voltage
F
0.35
YEL/BLK
1227
TFT Sensor Signal
G
0.35
BLK
452
Sensor Ground

Here's the PCM connections for the trans. You can see wire colors and circuit #'s coincide.

Awesome information!! Much appreciated. I went ahead and ordered both 96 and both 97 Riviera service manuals anyways to have it for the future. I will keep you guys updated on everything. So far I got some polished aluminum valve covers to put on since my gaskets are bad anyways. Sway bar end links, suspension off the 97 plus new top strut bushings or whatever they are called. I want to polish my supercharger up too to clean the bay up along with some stainless fuel rails. But first gotta get her running to take advantage over this warranty on the transmission.