Which TCM and/or after market

[DEA AK]

Just a question for anyone...

My truck is a 2003 M1097A2 and I am having issues that appear to be TCM or grounding / harness related...

First question, OEM TCM or after market like US Shift or similar?

If after market, which ones have been easily installed and reliable? Clearly there is something wrong with OEM TCMs since they seem to be commonly an issue.

If OEM... do I have to get the same exact model? For instance, mine is the TCM-2100BB... do I have to get the BB or would an AA, AB, BA or whatnot work?

My idea isn't to have a perfectly restored military truck, I want to to run well and be reliable. If after market is more reliable / durable / etc than OEM, please let me know.

Thanks,
David

 

[FlameRed]

I can only chime in regarding the aftermarket US Shift Quick 4, which I installed when I swapped out my TH400. Is is not cheap, for sure. There are others that are less expensive. US Shift tech support is great, so long as you call them - don't bother emailing, they won't respond. They now offer a report display which I love as they upgraded my older unit with out the remote display for $300.

The good thing about the US Shift is it is pretty straight forward to change the shift points with their software and a laptop. I had to tweak mine. Also, diagnostic messages in plain English come up on the remote display - not codes. The only negative is that I cannot seem to get their digital speedometer to be accurate. It is accurate a low speeds but off at higher speeds. I have not figured out how to make it accurate in all ranges.

Regarding reliability, I only once had an issues with the Quick Shift 4. I once started the truck and the remote display would not light up and the tranny would not shift out of 2nd. I pulled off the side of the road and turned the truck off and restarted and everything was fine. Never happened again. Not sure why.

It is a pretty easy install. Get their harness plain and cover it yourself to protect it. Don't try to make up your own harness unless you are expert at that sort of thing.

But before I would start swapping systems, I could recommend buying a can of electronic cleaner, and clean the tranny connector and the grounds. It might solve your issues cheaply.

 

[Mogman]

David, If you do not have 12V to the trans light connector it is not the TCM.
Your truck is shifting so it is a little premature to be looking for a TCM

 

[DEA AK]

David, If you do not have 12V to the trans light connector it is not the TCM.
Your truck is shifting so it is a little premature to be looking for a TCM

Hi, I did test, and I do have 12v at the tcm input so at least the tcm is seeing 12v there... And you are right, she is shifting and the shifts are good, it doesn't wind out, they are almost unnoticeable (not sure if that's a good thing). I am just not seeing how/where to trace the signal from the tcm to that light. I am kind of thinking it has something to do with that are of the truck since my transfer case lock light doesn't come on either. all the wires are plugged in down below.

 

[DEA AK]

I can only chime in regarding the aftermarket US Shift Quick 4, which I installed when I swapped out my TH400. Is is not cheap, for sure. There are others that are less expensive. US Shift tech support is great, so long as you call them - don't bother emailing, they won't respond. They now offer a report display which I love as they upgraded my older unit with out the remote display for $300.

The good thing about the US Shift is it is pretty straight forward to change the shift points with their software and a laptop. I had to tweak mine. Also, diagnostic messages in plain English come up on the remote display - not codes. The only negative is that I cannot seem to get their digital speedometer to be accurate. It is accurate a low speeds but off at higher speeds. I have not figured out how to make it accurate in all ranges.

Regarding reliability, I only once had an issues with the Quick Shift 4. I once started the truck and the remote display would not light up and the tranny would not shift out of 2nd. I pulled off the side of the road and turned the truck off and restarted and everything was fine. Never happened again. Not sure why.

It is a pretty easy install. Get their harness plain and cover it yourself to protect it. Don't try to make up your own harness unless you are expert at that sort of thing.

But before I would start swapping systems, I could recommend buying a can of electronic cleaner, and clean the tranny connector and the grounds. It might solve your issues cheaply.

Good copy, thank you for the info, I appreciate it.

 

[Mogman]

Hi, I did test, and I do have 12v at the tcm input so at least the tcm is seeing 12v there... And you are right, she is shifting and the shifts are good, it doesn't wind out, they are almost unnoticeable (not sure if that's a good thing). I am just not seeing how/where to trace the signal from the tcm to that light. I am kind of thinking it has something to do with that are of the truck since my transfer case lock light doesn't come on either. all the wires are plugged in down below.

That 12V does not come from the TCM, it comes from the trans relay.
The transfer case lock light has nothing to do with the trans light, it is run by 24V from the inst. power

 

[DEA AK]

That 12V does not come from the TCM, it comes from the trans relay.
The transfer case lock light has nothing to do with the trans light, it is run by 24V from the inst. power

copy, I will have to dig into that as well. thank you.