GM 6L80 Transmission Information Thread

[rbrickey37660]

This is speculation but seems as though there's a partial restriction in your system. The shop should have flushed the lines and cooler(s) prior to installation of the rebuilt transmission. Not sure why they are using Dorman but nothing that company makes is any good. They should have installed a GM OEM brand new TEHCM, IMS and speed sensor/harness assembly in addition to a whole host of other things. Then they would have had to program the TEHCM to your VIN as GM TEHCMs do not come pre-programmed.

Beyond that, it's up to them to get it right - nothing else for me to add.

Update.....the shop can't figure out what is going on...they have ordered a new transmission from dealer. They have built and put the 3 different transmissions in it and all 3 do the same thing...not holding lockup. They are saying that is why they are overheating and burning up.

 

[NickTransmissions]

Update.....the shop can't figure out what is going on...they have ordered a new transmission from dealer. They have built and put the 3 different transmissions in it and all 3 do the same thing...not holding lockup. They are saying that is why they are overheating and burning up.

My guess is the new one will also burn to the ground for the same reason. Three diff transmissions failing like that, same problem points to an issue with that vehicle or shop. Gotta find out which of those two is the source of the problem.