TCM to transmission pinout/diagram?

JAYJAY1985

MEMBER
2006 CHEVROLET 3500
6.6L
V8
4WD
AUTOMATIC
170,000 MILES

Hi I'm looking for a TCM to trans pinout/diagram. The truck is a 2006 Silverado 3500 cab and chassis Duramax with the Allison 6 speed. The harness got torn up and there's a couple of wires in there that are the same colors. Thank you

Wednesday, February 18th, 2026 AT 2:04 PM

4 Replies

AL514

MECHANIC
5,552 POSTS

Hello, I do see there are a couple wires the same color on the wiring diagrams, give me a few minutes to get these ready for you.

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Wednesday, February 18th, 2026 AT 7:44 PM

AL514

MECHANIC
5,552 POSTS

Here are the wiring diagrams for the Allison transmission, the aftermarket and oem wiring. With an inline connector and pinout. Hopefully this is the correct info you were looking for.

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