2016 Tahoe LTZ Transmission issue (P0741 Code)

[jrmhokie]

New member, apologies if there is already a thread on this but couldn't find it. 2016 Tahoe LTZ w/ roughly 130k miles, owned since 18k miles. Yesterday on the way home from the airport I noticed the transmission was acting differently. Check engine light came on so I pulled over and used my OBD2 scanner to read the warning light code. Came back as a P0741 "Torque Converter Clutch Circuit Performance/Stuck Off". The transmission performance issue I was seeing included (1) felt like it wasn't making it to 6th gear at highway speed (at 70mph is was running at or above 2500rpm) and (2) once I got off the highway I noticed that the car would not shift properly from a stop, with RPMs going well above normal before the car would shift gears. I took it to a local transmission shop this morning and where the technician hooked the shop scanner on and drove it around (with me in the car) for about 20mins before heading back to the shop where he said that he thought the best course of action would be to replace the transmission (am currently waiting on estimate). I'm no transmission expert so I'm looking for some additional brain power on what realistically is wrong and what a reasonable fix would be for this issue. @NickTransmissions any advice would be appreciated. Thanks in advance for your help.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I cannot personally assist you with your issue, but Nick and other members of this Forum much more knowledgeable than me in this area will chime in.

 

[jrmhokie]

 

[jrmhokie]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I cannot personally assist you with your issue, but Nick and other members of this Forum much more knowledgeable than me in this area will chime in.

okie dokie. pics to follow

 

[NickTransmissions]

what realistically is wrong and what a reasonable fix would be for this issue. @NickTransmissions any advice would be appreciated. Thanks in advance for your help.

P0741 is usually converter failure and converter failure usually equates to transmission failure, unfortunately.

Reasonable (and correct, sustainable) fix is to properly overhaul the unit and install an upgraded converter with a better clutch. Also flip the pill inside your thermal bypass valve.

While the factory TC is a POS, there's quite a few upstream drivers behind its frequent failures including worn TCC regulator valve (valve body), worn pressure regulator valve (pump), bad TEHCM (not as common as the previous two), excessive trans temps (moreso w/the K2 trucks/SUVs 2014+). Visit my 6L80 Info Thread for more details on these units - link is in my signature line.

 

[jrmhokie]

P0741 is usually converter failure and converter failure usually equates to transmission failure, unfortunately.

Reasonable (and correct, sustainable) fix is to properly overhaul the unit and install an upgraded converter with a better clutch. Also flip the pill inside your thermal bypass valve.

While the factory TC is a POS, there's quite a few upstream drivers behind its frequent failures including worn TCC regulator valve (valve body), worn pressure regulator valve (pump), bad TEHCM (not as common as the previous two), excessive trans temps (moreso w/the K2 trucks/SUVs 2014+). Visit my 6L80 Info Thread for more details on these units - link is in my signature line.

Thanks @NickTransmissions for the detailed response. Transmission shop said about the same thing and they told me they use an upgraded converter when they swap in a rebuilt transmission. They rebuild the TEHCM in their shop and end up replacing all the valves. I'll double check the when I drop the Hoe off this afternoon and will ask them about "flipping the pill". Appreciate your help.

 

[NickTransmissions]

Thanks @NickTransmissions for the detailed response. Transmission shop said about the same thing and they told me they use an upgraded converter when they swap in a rebuilt transmission. They rebuild the TEHCM in their shop and end up replacing all the valves. I'll double check the when I drop the Hoe off this afternoon and will ask them about "flipping the pill". Appreciate your help.

Ask them for specifics around 'rebuilding the TEHCM' as they ARE NOT REBUILDABLE! The pressure switch seals, diaphragms and TEHCM filter screen are all replaced during a service but the individual variable force solenoids are not individually replaceable. I'd want to know exactly what they mean by 'rebuilding the TEHCM'.

Valve body/pump/center support should have a Sonnax zip or Transgo Tow-N-Pro installed. Pump should be replaced with OEM GM new assembly or reman'ed completely, down to the stator-stator support gasket.