2012 Yukon Denali 6L80 Issues/Advice

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Pointer 21

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Good Morning Gurus! I'm new to the board but have been using it as a resource (Great One at that).

Quick Facts:

-2012 GMC Yukon Denali 152,000K miles
-Bought Brand New
- 0 problems to date

ISSSUE: I was running fine last week, felt something a LITTLE sketchy when shifting out of first (at a stop light).
Next day was driving on the freeway (AND ZOOOMMMM) RPMS hit 3,000 + and I'm doing 30 mph until I can get to the closest town.
After I set for awhile I was able to drive with little problems; HOWEVER, the engine light came on AND has sense turned off.

My question: I've been to one mechanic who had good reviews. He didn't even look at it and just said "yeah, I know what's going on $3300 for aftermarket parts and a rebuilt transmission".
I gather he knows his stuff; however, how do I know what's actually gone in that transmission? Seems to me like a Torque Converter would be necessary and whatever else. Also, he would be using Sonnax aftermarket parts? **Opinions here?***

Is this just a "fix it once and replace everything while you're in there approach" and is it advised?

I believe I will be needing work done to my Catalytic convertor and likely some suspension repairs in the near future.

Trying to figure out my total cost of ownership or if its time to abandon ship and move onto the next problem vehicle.

Any advice is appreciated - My apologies for the long post.
 
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wsteele

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My $.02 only.

When it comes to used cars/trucks, the devil you know is almost universally better than the devil you don't. If it isn't rusting out, it will be cheaper to have it fixed as needed than suffer the $10K a year in depreciation a new one provides. If the alternative is a new Toyota Corolla, then yes, it will be cheaper in the long run to make a change. But a Corolla is a far cry from what you have been driving for the last 152K miles. :)

As far as the transmission, I would get a second opinion from an equally highly rated source, maybe a dealer service manager if you can find a good one. I have a great local dealer (from the service department perspective), so if it were me, I would take it there too.

My personal bias is you likely are going to need some big stuff in the tranny/TC area. If the second opinion confirmed that, I would get a GM reman installed and move on to bigger and better things. I would not let a local shop "rebuild/upgrade" my daily driver, at least one I relied on for long distance travel. :)

It won't feel like it when you are writing those big checks, but it will be cheaper to keep it than buying a new one.
 
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Pointer 21

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My $.02 only.

When it comes to used cars/trucks, the devil you know is almost universally better than the devil you don't. If it isn't rusting out, it will be cheaper to have it fixed as needed than suffer the $10K a year in depreciation a new one provides. If the alternative is a new Toyota Corolla, then yes, it will be cheaper in the long run to make a change. But a Corolla is a far cry from what you have been driving for the last 152K miles. :)

As far as the transmission, I would get a second opinion from an equally highly rated source, maybe a dealer service manager if you can find a good one. I have a great local dealer (from the service department perspective), so if it were me, I would take it there too.

My personal bias is you likely are going to need some big stuff in the tranny/TC area. If the second opinion confirmed that, I would get a GM reman installed and move on to bigger and better things. I would not let a local shop "rebuild/upgrade" my daily driver, at least one I relied on for long distance travel. :)

It won't feel like it when you are writing those big checks, but it will be cheaper to keep it than buying a new one.
Thank you for the response and great advice (I KNOW what I SHOULD be doing but one can only dream about a "justifiable" reason to get something new.

That said - I talked to another shop and they're wanting $4,400 for a rebuild giving you a 2 Yr 24K mile warranty.
The other guy with the Sonax quote at $3,300, only warrants for 1 yr 12K.

The guy at $3,300 said that he does work for GM (charges them $3,300) and they turn around with their markup to the customer.

I guess the question is who to go with in that each place has it quirks but what I keep hearing is that GM really doesn't make these trannies to last longer than 120k miles....
 

wsteele

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I don’t think the advice you are getting on the longevity is correct. Many report double those mileages, I think to plan on 120K would be overly conservative.
 

Joseph Garcia

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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.

You are already receiving sage advice from the knowledgeable folks on this Forum.
 
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Pointer 21

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Thanks for the warm welcome - I don't have pics on hand (will post later). It's all stock with OEM 22's.

My goal is to not get hosed here. These transmission folks aren't really diagnosing the problem, just saying "rebuilt tranny, upgrade TC". This is on the phone.

Already busted one quoting me and slighly squeezing in that doesn't include any of the other parts (I guess the parts that wouldn't be in a rebuild kit).

My take is they give a price and go up on you, once your already into it.

I did like the guy who flat out said $3300,1 yr 12k mile warranty, sonnax parts. Less BS in his pitch than these other folks.....

Where to go, Where to go??
 

Geotrash

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Good Morning Gurus! I'm new to the board but have been using it as a resource (Great One at that).

Quick Facts:

-2012 GMC Yukon Denali 152,000K miles
-Bought Brand New
- 0 problems to date

ISSSUE: I was running fine last week, felt something a LITTLE sketchy when shifting out of first (at a stop light).
Next day was driving on the freeway (AND ZOOOMMMM) RPMS hit 3,000 + and I'm doing 30 mph until I can get to the closest town.
After I set for awhile I was able to drive with little problems; HOWEVER, the engine light came on AND has sense turned off.

My question: I've been to one mechanic who had good reviews. He didn't even look at it and just said "yeah, I know what's going on $3300 for aftermarket parts and a rebuilt transmission".
I gather he knows his stuff; however, how do I know what's actually gone in that transmission? Seems to me like a Torque Converter would be necessary and whatever else. Also, he would be using Sonnax aftermarket parts? **Opinions here?***

Is this just a "fix it once and replace everything while you're in there approach" and is it advised?

I believe I will be needing work done to my Catalytic convertor and likely some suspension repairs in the near future.

Trying to figure out my total cost of ownership or if its time to abandon ship and move onto the next problem vehicle.

Any advice is appreciated - My apologies for the long post.
The issue is that until he gets it apart, you won't know what failed. There's a decent chance that it's the TC - the lock-up clutch fails and sends shrapnel through the whole system. Then you need not only a new transmission, but the cooler and lines as well.

Apart from that issue, the 6L80E is usually pretty long-lived with proper maintenance. I have 215K on my 2007, and 130K on my 2012 with a lot of towing, and no issues. And, many problems can be fixed with the thing still in the vehicle by replacing some valve body components on the bench.
 
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Pointer 21

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The guy that is giving me a flat fee cost of $3300 (sight unseen) and warranty of 1 yr 12K miles with Sonnax parts (says he will not go higher on cost). Does this seem legit?
 

Geotrash

Dave
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The guy that is giving me a flat fee cost of $3300 (sight unseen) and warranty of 1 yr 12K miles with Sonnax parts (says he will not go higher on cost). Does this seem legit?
Sure, for a shotgun approach to a complete overhaul. Though I generally prefer mechanics who properly test and diagnose the problem and can clearly explain what it is and how they know.
 
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Pointer 21

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Sure, for a shotgun approach to a complete overhaul. Though I generally prefer mechanics who properly test and diagnose the problem and can clearly explain what it is and how they know.
That's my thought - He could hit a jackpot, salvage parts and I'd never know. There's another shop that is saying about $1,000 more BUT 2 year 24K warranty, and the 3rd saying $3300 but they don't include the unforeseeable (obviously they're going to pull something) BUT they'll give a 3 yr 36K warranty.

These trans places are sketchy. LOL
 

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