2015 Yukon 6.2-Listen to this noise- dealer says $5k for new TX

[07denaliyuk]

Looking for help with diagnosis and fix

2015 XL 6.2 with 6l80e
Transmission shudder driveline Noise at 1/3 throttle at all speeds after engine is warned up. No OBD codes

- TX mechanic ruled out the torque converter, wrong area for noise
- no metal in the oil
- no codes
- tachometer jumps 3-400 rpm when noise happens.
- u-joints are all good shape

Noise on highway

Noise with Camera in 3rd row

 

[Big Mama]

I’m not much help here but others will chime in. Welcome to the forum from Virginia.

 

[Tiredmechanic23]

Was the trans pan dropped? Any mods, tunes, etc to the vehicle? Where was the noise pinpointed to by the tech? did he listen from under it or only when driving or operating? I ask this as noise can echo and sound like its in one area but be in a completely different area in reality.

 

[mb1500]

Strange. Does it go away without throttle input?

 

[gat0r]

hadnt heard that ...yet


sounds like mechanic needs to move around inside while you are driving.
maybe use a gopro underneath too

 

[tirekicker]

i didn't know you could get the 6l80 with the l86. is it one of the very first production run?

 

[Doubeleive]

i didn't know you could get the 6l80 with the l86. is it one of the very first production run?

the first 6 months production had the 6 speed

 

[tirekicker]

interesting....

 

[07denaliyuk]

Strange. Does it go away without throttle input?

It’s intermittent, it goes away without throttle input.

 

[07denaliyuk]

Was the trans pan dropped? Any mods, tunes, etc to the vehicle? Where was the noise pinpointed to by the tech? did he listen from under it or only when driving or operating? I ask this as noise can echo and sound like its in one area but be in a completely different area in reality.

Have not dropped the pan yet, likely this week.
No modifications to the engine or transmission, all stock.
The dealer tech only drove it a few miles, I don’t know if they put an real effort into diagnosing it. It’s likely they deemed it a torque converter since they fail at a high rate and just said ‘new trans’.
Local trans guy initially said torque converter but after a test drive, he hadn’t heard this issue before. He thought possible electronic issue in valve body.

 

[mb1500]

What is the condition of the trans fluid?

 

[avalonandl]

Clutch pack is my UNEDUCATED GUESS....but a rebuild SB about 3200$

 

[JerradT]

does it do that if you put trans in manual mode (manual mode prevents from switching back & forth to 4cyl mode)
when we first bought our 15' suburban with 5.3 it would have intermittent shuddering while driving on the highway. turns out it was the exhaust valve near the muffler that opens & closes when it goes into 4cyl mode. it has a spot where it can be blocked permanently open for test purposes. luckily the dealer we bought it from replaced the exhaust for us since we noticed the issue right away. not for sure if the 6.2 has the same style exhaust system with the valve but if it does may check that out.

 

[Tiredmechanic23]

Have not dropped the pan yet, likely this week.
No modifications to the engine or transmission, all stock.
The dealer tech only drove it a few miles, I don’t know if they put an real effort into diagnosing it. It’s likely they deemed it a torque converter since they fail at a high rate and just said ‘new trans’.
Local trans guy initially said torque converter but after a test drive, he hadn’t heard this issue before. He thought possible electronic issue in valve body.

The pan will tell us a lot. There are a few odd clunks other than the trans it could be but im going to guess thats what it is for now.

Clutch pack is my UNEDUCATED GUESS....but a rebuild SB about 3200$

Performance rebuild is very little more for much better build than stock. TK Performance is who built mine. I give them credit for being quick and answering their phone and offering advice. https://www.tkperformanceandauto.com/products/6l80e-tkr-transmission

does it do that if you put trans in manual mode (manual mode prevents from switching back & forth to 4cyl mode)
when we first bought our 15' suburban with 5.3 it would have intermittent shuddering while driving on the highway. turns out it was the exhaust valve near the muffler that opens & closes when it goes into 4cyl mode. it has a spot where it can be blocked permanently open for test purposes. luckily the dealer we bought it from replaced the exhaust for us since we noticed the issue right away. not for sure if the 6.2 has the same style exhaust system with the valve but if it does may check that out.

This is another possibility as well to look at.

 

[07denaliyuk]

Dropped the pan.
- oil has a strong burnt smell to it.
- small amount metal flit around the magnet

I’ll replace the filter and refill with new tx oil and see if there’s an improvement.

Damn you GM for making me drop the exhaust to drop the pan.

 

[Tiredmechanic23]

It looks like your on the early signs of a trans failure. You will likely get more out of it but be prepared to rebuild/replace it. No yellow metals so im guessing clutch and steels.

Also the exhaust drop for the trans service is BS lmao. I hate it.

 

[Big Mama]

Any chance your power train warranty is still in tact?

 

[07denaliyuk]

Any chance your power train warranty is still in tact?

Sadly No, 150k miles on this tx

 

[Jeramia]

Sadly No, 150k miles on this tx

Remove transmission pan. Remove two bolts from the trans. rear mount. jack back of trans. up as high as it will go. Twist pan to left, comes right out.

 

[mb1500]

Yeah that fluid looks pretty bad...