Run transmission with no program in TEHCM

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

skpyle

Senior Member
Supporting Member
Joined
May 15, 2021
Posts
521
Reaction score
1,305
Hello Gentlemen!

I am inching ever so closer to starting the overhauled 6.2L engine in my 2013 Escalade. See this thread for context: https://www.tahoeyukonforum.com/threads/2013-escalade-esv-dod-full-delete-becoming-rebuild.156091/

As part of the scope of the work, I had the 6L80 transmission overhauled by a local shop. I had a new GM TEHCM installed. Meaning it has no program. In the past, it has been possible to connect my laptop to my Tech 2 clone, buy a month subscription to a GM website, and download a program into my TEHCM. If I understand correctly, that is no longer possible, or is very difficult to do.
I am going to have my Escalade flatbedded to the shop that overhauled the transmission, and have them download a program into the TEHCM.

Before then, I want to start and run the engine. The transmission will have fluid in it. Here is my line of thinking: The TEHCM controls the solenoids for shifting and line pressure. It responds to the pressure switches. Meaning all of this is used to make the transmission do transmission things. The fluid pump is purely mechanical. Meaning if the torque converter is turning, the pump is turning, moving fluid. The fluid should flow to everywhere it needs to go. The TEHCM not having a program should not affect this. It should not hurt the transmission to run the engine with the TEHCM non functional.

Does this make any sense?

I understand the CEL will be illuminated from no comms with the TEHCM. The engine 'should' still start.

I want to start and run in the overhauled engine at home, not at the transmission shop...


Sooooo...does anyone have any experience or thoughts on what I am trying to do?


Thanks for your time!
 

Joseph Garcia

Elite Member
Supporting Member
Joined
Aug 2, 2018
Posts
10,267
Reaction score
14,870
You are correct in that the Tech 2 is no longer supported by the GM website for programming purposes.
 

j91z28d1

Full Access Member
Joined
Feb 28, 2022
Posts
4,599
Reaction score
5,860
for a 140$ I had good luck with the OBDX pro gt dongle to flash modules on my yukon and volt.

I never even tried my tech 2. sounded like a hassle.
 

rdezs

Full Access Member
Joined
Nov 6, 2023
Posts
1,286
Reaction score
2,359
I definitely would not start the engine without programming the transmission....
 
OP
OP
skpyle

skpyle

Senior Member
Supporting Member
Joined
May 15, 2021
Posts
521
Reaction score
1,305
for a 140$ I had good luck with the OBDX pro gt dongle to flash modules on my yukon and volt.

I never even tried my tech 2. sounded like a hassle.
Good to know, I did not know that. Thanks!



I definitely would not start the engine without programming the transmission....
That is all I need to know. Thank you!



Have you spoken about this with your tuner?
For the 'tune' in the transmission, I have not talked to Blackbear. I will put the Blackbear TCM tune back in the TEHCM once everything is running. Blackbear informed me that I have to have the 'base tune' in teh TEHCM before the Blackbear tune can be put in.

For the transmission shop, they know that I am going to bring my Escalade to them to put a base tune in the TEHCM.




Alright, this tells me what I need to know.

Once I have my Escalade back together, I will have it flatbedded to the transmission shop. I will have them put a base tune in the TEHCM, but NOT start the engine in any way.

I will have my Escalade flatbedded back to my home. Where I will start everything.



Thanks for all your advice!
 

Forum statistics

Threads
137,672
Posts
1,989,114
Members
102,675
Latest member
j_jerry79

Latest posts

Back
Top