Torque converter issues

[NickTransmissions]

So the techm needs to be replaced every once in a while or the new ones are different then the stock ones? Sorry for all the questions and appreciate all the insight !!

Its recommendated that you replace every 100k so id prob have it done so you know its good to go. And for this, id go to the dealership so you know youre getting a genuine GM part and they can do the fast-adapt relearn for you. Don’t want any aftermarket electronics in the vehicle…

 

[Joseph Garcia]

It is GREAT to have a transmission specialist in the Forum!

 

[chartersj]

Its recommendated that you replace every 100k so id prob have it done so you know its good to go. And for this, id go to the dealership so you know youre getting a genuine GM part and they can do the fast-adapt relearn for you. Don’t want any aftermarket electronics in the vehicle…

Interesting. I'm going to call my dealer and ask about this job. Buddy of mine also has a yukon like mine 2017 also and his transmission went out at 180000kms. So this is why I got looking into this.

 

[chartersj]

It is GREAT to have a transmission specialist in the Forum!

Absolutely! I wouldnt have known about any of this had he not commented

 

[NickTransmissions]

Interesting. I'm going to call my dealer and ask about this job. Buddy of mine also has a yukon like mine 2017 also and his transmission went out at 180000kms. So this is why I got looking into this.

Yea, see what the service tech recommends insofar as flushing, TCM / TECHM replacement, etc...they may elect to function test and if everything's good, defer replacement which may save you some coin as those things aren't cheap.

 

[chartersj]

Yea, see what the service tech recommends insofar as flushing, TCM / TECHM replacement, etc...they may elect to function test and if everything's good, defer replacement which may save you some coin as those things aren't cheap.

Service tech recommended a fluid change only. They don't like to do the filter because of the seal apparently. I feel like I want the filter changed as it never has been. Also would like to add a pan with a drain plug so I can do more regular changes.
And I am also going to change the Thermal bypass valve to the new one so the transmission runs cooler.

 

[NickTransmissions]

Service tech recommended a fluid change only. They don't like to do the filter because of the seal apparently. I feel like I want the filter changed as it never has been. Also would like to add a pan with a drain plug so I can do more regular changes.
And I am also going to change the Thermal bypass valve to the new one so the transmission runs cooler.

Those are all good ideas…the filter pick up seal can be tricky to get to without dropping the control assembly out of the way but that seal usually isnt a problem. That said it may be a liability issue for them if the seal isn’t replaced when doing a filter and perhaps to replace it requires them to drop the control/valve assembly thus adding $$$ to the job. Just a guess…

I’d want to see whats in the pan and how much clutch material may be present as well…

 

[Thrust]

I'll add this, I called my local GM dealer last week to inquire how much a fluid and filter change would cost on my Cadillac CT6 (8 speed), and was kind of scolded for asking that the filter be changed. I was informed by a seasoned service advisor that the filter "is a screen to catch large particles and didn't need to be changed." He stated all I needed to do was flush the system and explained to me that process would get 99% of the fluid where as a filter change wouldn't. What bothered me is that the CT6 owners manual chart for maintenance intervals, normal driving, doesn't have a line item for the transmission. You have to go to the next page/chart for severe driving that then lists the transmission, which states to replace the fluid AND filter at 45k miles, and at every 45k mile intervals.
So be careful what the dealership states.

 

[chartersj]

I've decided to do this myself. I want to see how much filings is in the pan and I want the filter changed. I will use my vacuum pump through the dip stick tube to remove most of the fluid before dropping the pan. I'm thinking I could just use the pump in between filter changes to do a half oil change

 

[NickTransmissions]

I'll add this, I called my local GM dealer last week to inquire how much a fluid and filter change would cost on my Cadillac CT6 (8 speed), and was kind of scolded for asking that the filter be changed. I was informed by a seasoned service advisor that the filter "is a screen to catch large particles and didn't need to be changed." He stated all I needed to do was flush the system and explained to me that process would get 99% of the fluid where as a filter change wouldn't. What bothered me is that the CT6 owners manual chart for maintenance intervals, normal driving, doesn't have a line item for the transmission. You have to go to the next page/chart for severe driving that then lists the transmission, which states to replace the fluid AND filter at 45k miles, and at every 45k mile intervals.
So be careful what the dealership states.

Your experience is why I provide my own written maintenance guidance for all my rebuilds, which sometimes significantly deviates from what the dealers call for.

For example, BMW eliminated dipsticks in their transmissions sometime in the last 10-15 years or so and started specifying that transmission fluid was “lifetime”. To BMW: LOL what does that mean? Lifetime of the unit itself between overhauls, expected lifetime of the transmission or vehicle, lifetime of the owner? Unless some chemical science breakthroughs happened with trans fluid recently, it still wears out and needs to be changed after a period of time. And what happens when a filter can no longer “store” crud, debris and other stuff? Does it empty itself and make the debris disappear on its own?

I provide a service interval sheet for such units and directions for how to refill the fluid once the old fluid is emptied, new filter/gasket installed and pan is back on.