6L80 transmission swap
- Thread starter MadMax1
- Start date
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swathdiver
Full Access Member
The shop replacing the transmission ought to be doing this for you. If you are doing this, you'll need a laptop, an MDI or MDI2 or similar device and a subscription to ACDelco's TDS service to do the programming through the OBDII port.
If you reuse and or overhaul your TECHM, you won't have to replace it but should perform the Service Learn Adapts with a bi-directional scan tool.
From my understanding, this is attached to the valve body. My valve body is toast so I dont think I can keep the tcm.
yes it needs a relearn any halfway decent scanner can do it, if the shop does not have a scanner to do it which is VERY standard procedure, then find another shop.....
if you are doing it yourself then you can have it towed to any shop with a scanner to do it afterwards or have a mobile mechanic come do it or buy a scanner which is a investment that pays for it's self.
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swathdiver
Full Access Member
The TECHM does attach to the valve body but they can be overhauled or replaced. Use GM OE only or whatever @NickTransmissions recommends. Several years ago the Dorman ones had a high failure rate.
Top add to what's already been said, the device linked below plus a Windows 10/11 laptop, plus a 3-day subscription to ACDelco TDS will allow you to do the programming if your shop can't (they should):
I have one. Works flawless!
I believe it's $45 bucks for a year or up to the amount of modules your truck has.
@MadMax1 - Assuming you're still viewing the forum, the folks posting above have the re-learn aspect covered (though very late model 6Ls did away w/the fast relearn from my understanding) so if you have something in the 2018-2020 timeframe, you may not need to do the relearn. That said, no movement in any range position can be valve body as well as TEHCM, pump or internal case. Not sure if you've actually diagnosed the no-movement condition/pinpointed the direct cause(s) but if you haven't I'd pull the VB down, split it and look for worn check balls...The #1 and #5 are the guilty parties when it comes to wear-driven no movement conditions.
Here's a quick video i did on the subject:
Here's a quick video i did on the subject:
