M6 swap. couple ?'s
Thread Starter
Joined: Nov 2005
Posts: 515
Likes: 0
From: North Augusta, SC
M6 swap. couple ?'s i will be swapping in the complete t56 set-up from my green car into the red a4 car in my sig. i've found plenty of info on the swap, but nothing really specific to how i'm planning on doing it. obviously i have a complete donor car with every part i could possibly want to use to do this. that being said, i will have about a 8 days to get the swap done start to finish.
my main questions right now involve to wiring.
-would it be easier/faster to swap the interior harnesses or simply modify them with the correct pigtails? i can wire pretty well so i'm not worried about that, and if i have to pull the carpet or dash to swap the harnesses i'd rather just modify the existing one with the pigtails to keep labor and time down. if modifying the harness is easier, where can i get the specific connectors?
-what other parts of the wiring harness need to be swapped? i assume the t56 has some sort of transmission side wiring extension that includes everything for it. should i swap both entire engine bay harnesses while the motors are out?
-do i need to swap in the m6 pcm or would doing it make the swap easier? i've seen some mention of re-pinning parts of it. i don't see why i would do this if i have an m6 pcm sitting there. just need some clarification
-if i do swap pcm's, i will have to sort out the VATS issue correct? if so would it be faster to bypass it or just swap the steering columns/ignition cylinders?
just trying to make sure i have all of this ready to go before i get started. i want to avoid as many hang-ups as possible
my main questions right now involve to wiring.
-would it be easier/faster to swap the interior harnesses or simply modify them with the correct pigtails? i can wire pretty well so i'm not worried about that, and if i have to pull the carpet or dash to swap the harnesses i'd rather just modify the existing one with the pigtails to keep labor and time down. if modifying the harness is easier, where can i get the specific connectors?
-what other parts of the wiring harness need to be swapped? i assume the t56 has some sort of transmission side wiring extension that includes everything for it. should i swap both entire engine bay harnesses while the motors are out?
-do i need to swap in the m6 pcm or would doing it make the swap easier? i've seen some mention of re-pinning parts of it. i don't see why i would do this if i have an m6 pcm sitting there. just need some clarification
-if i do swap pcm's, i will have to sort out the VATS issue correct? if so would it be faster to bypass it or just swap the steering columns/ignition cylinders?
just trying to make sure i have all of this ready to go before i get started. i want to avoid as many hang-ups as possible
i did mine by myself for the most part in a single weekend. I drove to my dads on friday as an automatic and drove home sunday as a manual.
-I just modified the stock wiring harness. (very simple since the main wires are already there, they just need to be rewired into the manual transmission pigtails)
-I bought a few transmission pigtails from gm since i didnt have any from a donor car like you will.
-I had to get a chip burned to correct my speedo since i have a 1993.
- the carpet doesn't need to be removed.
-installing the pedals is a pain in the ***
-install the bellhousing then install the transmission.
-i didnt have to re-pin anything
-the wires that need to be modified are under the car.
this is the ultimate write-up...i printed it out and used it when doing my swap
http://www.afrashteh.com/tranny_pics/T56.htm
-I just modified the stock wiring harness. (very simple since the main wires are already there, they just need to be rewired into the manual transmission pigtails)
-I bought a few transmission pigtails from gm since i didnt have any from a donor car like you will.
-I had to get a chip burned to correct my speedo since i have a 1993.
- the carpet doesn't need to be removed.
-installing the pedals is a pain in the ***
-install the bellhousing then install the transmission.
-i didnt have to re-pin anything
-the wires that need to be modified are under the car.
this is the ultimate write-up...i printed it out and used it when doing my swap
http://www.afrashteh.com/tranny_pics/T56.htm
Thread Starter
Joined: Nov 2005
Posts: 515
Likes: 0
From: North Augusta, SC
thats actually the link i've been looking at a lot. so what exactly has to be done on the inside? i won't need to do any wiring i don't think because i'll just be swapping the t56 harness with the motor and trans also
the engine harness will plug right in to the existing dash harness... the only extra thing i can think of when i did mine was i bought the Clutch Start Switch.. basically is when you go to start the car you must have the clutch pushed in switch.. its 2 wires and they go to the wiring harness that plugged into the Automatic shifter.. just have to pull the diagram to figure out which 2 wires it goes to.
you will have to pull out the steering column and center console. then you have to use a hole saw to make a hole for clutch master cylinder (there is a little indentation where it goes) and then you get to make a hole for the shifter. it will be alot easier than you think once you start tearing into the job. especially since you have a parts car. i just had a **** load of parts sitting around lol
i left my seats in the car too. i didn't care about the old transmission lines that connect to the radiator, so i cut those out and plugged the radiator holes.
Last edited by The Batman; Feb 16, 2011 at 04:04 AM.
Thread Starter
Joined: Nov 2005
Posts: 515
Likes: 0
From: North Augusta, SC
sorry to bump this up again guys, but got another question.
i finally found the wires i have to connect to the clutch switch, wish the write-up would have said they were on the old a4 shifter harness instead of under the dash. posting that so if someone else needs to search, here it is
so my question is with the reverse light wiring. with having the m6 engine harness and trans connectors, do i still need to connect the a4 wires for the reverse lights or will it be fine to just leave the m6 connections on? i'll be using the m6 pcm
i finally found the wires i have to connect to the clutch switch, wish the write-up would have said they were on the old a4 shifter harness instead of under the dash. posting that so if someone else needs to search, here it is
so my question is with the reverse light wiring. with having the m6 engine harness and trans connectors, do i still need to connect the a4 wires for the reverse lights or will it be fine to just leave the m6 connections on? i'll be using the m6 pcm
Trending Topics
TECH Enthusiast
Joined: Feb 2005
Posts: 633
Likes: 4
From: Phoenix, AZ
I used all existing wires in the car for mine to work. Everything you need is in the A4 bulk connector and the A4 neutral safety switch. The A4 uses the neutral switch for the reverse lights if I remember correctly. Its been too long since I did mine, need to get another under my belt. 
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Great to know, i have done one complete swap but the car was sold before it was driven so no idea if all the wiring was correct and the other car is ready for the parts to be put in but the engine still isn't ready so the one im doing to my car right now will be the first to actually hit the road and the wiring is the inly thing im really worried about.
