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E40/T42 Experts - please help

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Old Sep 6, 2017 | 06:09 PM
  #1  
Lukaniuk's Avatar
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Default E40/T42 Experts - please help

TL;DR - is there a compatability issue between the E40 and 17 Pin 4L60E T42? how to test for this?

The long version:

I am trying to use an E40 LS2 from a 2006 TBSS and a 17 pin 4L60E from a 2009 Silverado (4.8L) in. It runs and drives, but shifts really hard.

The scan shows the transmission is at max line pressure and it's trans pressure Mode is "Diag Max". I do get a U0101 code.

I am using the ECM from the Trailblazer, TCM from the pickup, and I have modified the TBSS harness to fit the 17 pin connector on the transmission like so:

Trans (17 pin) ---> T42
A (1-2 Shift Solenoid Valve Control) ---> T42-Pin 2
B (2-3 Shift Solenoid Valve Control) ---> T42-Pin 20
C (PC Solenoid Valve High Control (Sol. A)) ---> T42-Pin 40
D (PC Solenoid Valve Low Control (Sol. A)) ---> T42- Pin 17
E ---> +12V
F (Trans Range Signal A) ---> T42-Pin 29
G (Trans Range Signal B) ---> T42-Pin 46
H (Trans Range Signal C) ---> T42-Pin 23
J (Trans Range Signal P) ---> T42-Pin 39
K (ISS Signal) ---> T42-Pin 3
L (TFT Sensor Signal) ---> T42-Pin 35
M (Low Reference) ---> T42-Pin 30
N ---> Ground
P
R
S
T (TCC Soln Valve Control) ---> T42-Pin 25
U (TCC PWM Soln Valve) ---> T42-Pin 1
V (Low Reference) ---> T42-Pin 45
W (Park / Neutral Signal) ----> Nothing

Scans show I am registering the trans temp, input speed, output speed, PRNDL status and current gear, so I am hoping its a wiring issue on the Trans Range Signal wiring.

I am tearing into my wiring to double check everything, but is is possible the issue is an incompatability with the E40 and T42? Is there a way to test this?
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Old Sep 6, 2017 | 06:29 PM
  #2  
Lukaniuk's Avatar
Thread Starter
Teching In
 
Joined: Jul 2012
Posts: 2
Likes: 0
Default LS2 E40 and 17 pin 4L60E

Hi folks, I've been watching and learning silently for a while now while I've been doing my swap and I'm sorry my first post is only after I've run into a technical roadblock.

TL;DR - is there a compatability issue between the E40 and 17 Pin 4L60E T42? how to test for this?

The long version:

I am trying to use an E40 LS2 from a 2006 TBSS and a 17 pin 4L60E from a 2009 Silverado (4.8L). It runs and drives, but shifts really hard.

The scan shows the transmission is at max line pressure and it's trans pressure Mode is "Diag Max". I do get a U0101 code (lost comm with TCM).

I am using the ECM from the Trailblazer, TCM from the pickup, and I have modified the TBSS harness to fit the 17 pin connector on the transmission like so:

Trans (17 pin) ---> T42
A (1-2 Shift Solenoid Valve Control) ---> T42-Pin 2
B (2-3 Shift Solenoid Valve Control) ---> T42-Pin 20
C (PC Solenoid Valve High Control (Sol. A)) ---> T42-Pin 40
D (PC Solenoid Valve Low Control (Sol. A)) ---> T42- Pin 17
E ---> +12V
F (Trans Range Signal A) ---> T42-Pin 29
G (Trans Range Signal B) ---> T42-Pin 46
H (Trans Range Signal C) ---> T42-Pin 23
J (Trans Range Signal P) ---> T42-Pin 39
K (ISS Signal) ---> T42-Pin 3
L (TFT Sensor Signal) ---> T42-Pin 35
M (Low Reference) ---> T42-Pin 30
N ---> Ground
P
R
S
T (TCC Soln Valve Control) ---> T42-Pin 25
U (TCC PWM Soln Valve) ---> T42-Pin 1
V (Low Reference) ---> T42-Pin 45
W (Park / Neutral Signal) ----> Nothing

Scans show I am registering the trans temp, input speed, output speed, PRNDL status and current gear, so I am hoping its a wiring issue on the Trans Range Signal wiring.
Reply




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