Allison swap questions.

Ok, I am going 18 AWG for anyone wondering. I was digging through my stash of wiring and found some 18 AWG wire. First there's no way I would go smaller, second, it matches the wire on a pigtail I have. I would not mind going bigger, but the pins are only made for as big as 18 AWG. So 16 AWG might not work. I would be tempted to try though.
 
Another question.

Where are you all mounting the TCM?

Chevy I believe has it under the hood up close to the fan shroud.

I have seen them mounted on the side of the transmission in MD applications. And in swaps. Is this a safe place to out it? I mean would it not have a high chance of being damaged from weather and rocks from gravel roads?

I have also seen them on top of the transmission MD aplications.

I get that it takes less wite to do so. But is that worth it? After all wite is cheap compared to a new or even used TCM.

I am leaning towards under the hood mounted to the firewall right above the PCM. I could put it closer to the front and mount it to the battery tray if it needs more cooling.

Is cooling something I need to be concerned about?
What do you all think?
 
Well after working on some rollbacks that have the TCM mounted above the tail housing, and all the grime / oil leaks that cover them, I wouldn't hesitate to put it there in fear of a failure
 
pushlar84 said:
Inside fender on drivers side
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Thank you for your thoughts. That sounds like a
good place.

JWhite said:
Well after working on some rollbacks that have the TCM mounted above the tail housing, and all the grime / oil leaks that cover them, I wouldn't hesitate to put it there in fear of a failure
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I hear you. It's just hard to think of mounting that expensive of a piece to the transmission that is sitting in the elements. But like you said, if it's done from the factory like that, then it must be ok. Ot would be the simplest with the least amount of wire.

Thank you.

thatguy69 said:
I'm planning on putting mine above your feet on the drivers side inside firewall.
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When you say inside firewall. Are you meaning in the cab?
 
Cowboys4Christ said:
Thank you for your thoughts. That sounds like a
good place.



I hear you. It's just hard to think of mounting that expensive of a piece to the transmission that is sitting in the elements. But like you said, if it's done from the factory like that, then it must be ok. Ot would be the simplest with the least amount of wire.

Thank you.



When you say inside firewall. Are you meaning in the cab?
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Yep in the cab.
 
Cowboys4Christ said:
Ok. Are you planning to run the wire into the cab than do the pinout on the connector? That's a big plug to make a hole for otherwise.

I do plan on putting the BCM under the dash by the steering column.

What gauge wire are you using?
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Yeah I plan on pinning the connector once through the firewall. I'm going through the hole in the firewall where my slave cylinder went through.i bought Jason's diy kit where he sends you the wiring/connectors and then you build the harness yourself. I just opened it up and took a quick peak as I'm not ready for it yet. Finishing up putting the billet goodies in my trans now. The wiring he sent me was 18 and 16ga and there's a few twisted pair
 
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Ok. Sounds good. Going through the master cylinder spot in the firewall is a good idea. I like that. I am getting the pins that will work with 16 or 18 gauge to keep my options open. I am sure the twisted pairs are 18 gauge. That's how GM does it atleast. Speed sensors. I think there is up to three twisted pairs depending on how a guy does it. With the MD there might be just two. You would know though since you have the kit. Jason's kit is a good way to go. I am a little hard headed though and trying to do it all myself. Might not be good....

Nice, glad to hear your project is moving along. What all billet parts did you go with?
 
Cowboys4Christ said:
Ok. Sounds good. Going through the master cylinder spot in the firewall is a good idea. I like that. I am getting the pins that will work with 16 or 18 gauge to keep my options open. I am sure the twisted pairs are 18 gauge. That's how GM does it atleast. Speed sensors. I think there is up to three twisted pairs depending on how a guy does it. With the MD there might be just two. You would know though since you have the kit. Jason's kit is a good way to go. I am a little hard headed though and trying to do it all myself. Might not be good....

Nice, glad to hear your project is moving along. What all billet parts did you go with?
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TCS input/output/c2 hub and goerends p2. Overkill but I don't like doing things twice, or being broke down.
 
The other option is to bulkhead all the harnesses that pass thru the sheet metal. Yes it uses more parts but is nice for troubleshooting and replacement.
 
I see your point. OEM's use them all the time. It is one more fail point. But a little electrical grease would take care of the corrosion part of it.
 
i see more chafe shorts than bulkhead failures...

Corrosion has a lot to do with the quality of the connector. There are some euro products that are amazing.
 
sootie said:
i see more chafe shorts than bulkhead failures...

Corrosion has a lot to do with the quality of the connector. There are some euro products that are amazing.
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I agree, I also use electronic grease on all my connectors.

I do like your idea though! Thanks for the idea.
 
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