Transmission Issues - shaking, hard shift, should this be warrantied?

[Thuhreb]

2015 Yukon Denali 8 speed transmission 6.2L Engine, still under powertrain warranty

Had issues with vehicle sometimes jolting forward as we were coming to a stop, also occasional hard shifting.

Took it to local GMC dealership. They said it's a known issue with programming and they would need to reprogram the entire computer system. They said it's not a recall and not covered under our existing powertrain warranty because it's "not a part failure of the transmission". Then said it would cost us $525 for them to reprogram.

Is this BS?
Should I call GM directly?
Do they have to reprogram all systems or just the TCM?
Would this be covered on the federal emission warranty (we are under 80k miles)?
Side question, if they reprogram everything, might that enable apple carplay?

 

[swathdiver]

IDK the answers to your questions but for that much money I'd let BlackBear tune it properly and be done with it. Money well spent.

 

[cardude2000]

2015 Yukon Denali 8 speed transmission 6.2L Engine, still under powertrain warranty

Had issues with vehicle sometimes jolting forward as we were coming to a stop, also occasional hard shifting.

Took it to local GMC dealership. They said it's a known issue with programming and they would need to reprogram the entire computer system. They said it's not a recall and not covered under our existing powertrain warranty because it's "not a part failure of the transmission". Then said it would cost us $525 for them to reprogram.

Is this BS?
Should I call GM directly?
Do they have to reprogram all systems or just the TCM?
Would this be covered on the federal emission warranty (we are under 80k miles)?
Side question, if they reprogram everything, might that enable apple carplay?

I’m still under warranty and have held off on getting the transmission reprogrammed. My understanding is that the improvements are marginal and I’ve even heard some people say that it’s gotten worse after the reprogram. Others who have gotten it done here maybe can chime in.

I will say that mine seems to be getting worse over time.

 

[Tahoe14]

No on apple car play.

 

[CMoore711]

Complete ******** from that dealer.

I own 2015 Yukon XL Denali that I bought CPO. A little over a month ago my local dealer did a complete transmission fluid flush and refill with GM’s new recommended trans fluid and installed an update to my TCM all under warranty. Didn’t pay a penny.

I didn’t think it would make too much of a difference. But since they did this service absolutely no issues or intermittent jumps or hard shifts experienced. Starts and takes off smoother too.

Find a new dealer that knows what they’re doing, is willing to actually look into issues and perform the service in your best interest instead of their own. Then never return back to whatever dealer tried to tell you that BS for anything.

 

[dszx13]

What issue are you having? The 8 spd shudder? I've done a few fluid flushes. Using Mobil 1 full synthetic trans fluid. If that doesn't eliminate the shudder warranty pays for a converter. Done a few if them lol.

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[CMoore711]

What issue are you having? The 8 spd shudder? I've done a few fluid flushes. Using Mobil 1 full synthetic trans fluid. If that doesn't eliminate the shudder warranty pays for a converter. Done a few if them lol.

Sent from my SM-G928V using Tapatalk

This is the symptoms mine was doing. And I thought for sure after reading some of the TSB’s how could just a trans flush and TCM solve it but it did.

OP i think there’s a TSB on the shudder with the trans fluid flush and TCM flash update as the potential fixes. I don’t know for certain but try TSB#PIP5337E? Find the TSB print it off and take it to your dealer and see what they say...?

 

[dszx13]

This is the symptoms mine was doing. And I thought for sure after reading some of the TSB’s how could just a trans flush and TCM solve it but it did.

OP i think there’s a TSB on the shudder with the trans fluid flush and TCM flash update as the potential fixes. I don’t know for certain but try TSB#PIP5337E? Find the TSB print it off and take it to your dealer and see what they say...?

When the issue first started i was doing 3 flushes. Now gm says 1 flush of the cooler lines, new filter, and the Mobil 1 fluid. I've done dozens of trucks and suvs and only had to put 2 or 3 converters in afterwards.

Sent from my SM-G928V using Tapatalk

 

[CMoore711]

When the issue first started i was doing 3 flushes. Now gm says 1 flush of the cooler lines, new filter, and the Mobil 1 fluid. I've done dozens of trucks and suvs and only had to put 2 or 3 converters in afterwards.

Sent from my SM-G928V using Tapatalk

You’re right that is a slight change, good catch. Yes when mine was done it too was 3 flushes.

 

[Thuhreb]

Complete ******** from that dealer.

I own 2015 Yukon XL Denali that I bought CPO. A little over a month ago my local dealer did a complete transmission fluid flush and refill with GM’s new recommended trans fluid and installed an update to my TCM all under warranty. Didn’t pay a penny.

I didn’t think it would make too much of a difference. But since they did this service absolutely no issues or intermittent jumps or hard shifts experienced. Starts and takes off smoother too.

Find a new dealer that knows what they’re doing, is willing to actually look into issues and perform the service in your best interest instead of their own. Then never return back to whatever dealer tried to tell you that BS for anything.

Which warranty did they cover that under? I have power train, not bumper to bumper.