2012 Yukon Denali 6L80 Issues/Advice

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Geotrash

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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
They are, though I've found a good one here locally through Google Maps reviews. Super solid. They sourced and installed an upgraded billet torque converter for me because I tow a 7000 lb camper and knew it would eventually grenade the OEM unit. Lots of positive reviews on these guys, and that reflected my experience as well.
 

swathdiver

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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.
A GM reman carries a 100K mile warranty and can be serviced nationwide. I would put a scan tool on it and would be inclined to only fix what broke. When a simple part inside a transmission breaks, the trans shops ALWAYS wants to replace the whole thing. That's not always a bad thing either.

These transmission last about 160K when they are not serviced properly. When they are serviced properly they easily go 300K and last month we saw one drive into a shop with 410K for overhaul.

How many times have you changed the fluid?

Get the trouble codes and we can almost always tell what's wrong and what really NEEDS fixin'.
 

wsteele

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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
It may come down to the fact that he does this stuff every day and knows what the nominal cost is going to be and knows the standard deviation he is dealing with, so can offer with confidence a complete package for $3300.

From my perspective a GM reman is going to have everything to spec or better and is a known quantity with warranty that travels everywhere in the country. As far as the guy stating he does transmissions for GM, so the difference is just their markup? I think I would need a little proof of those claims before assuming he is telling the truth.
 
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A GM reman carries a 100K mile warranty and can be serviced nationwide. I would put a scan tool on it and would be inclined to only fix what broke. When a simple part inside a transmission breaks, the trans shops ALWAYS wants to replace the whole thing. That's not always a bad thing either.

These transmission last about 160K when they are not serviced properly. When they are serviced properly they easily go 300K and last month we saw one drive into a shop with 410K for overhaul.

How many times have you changed the fluid?

Get the trouble codes and we can almost always tell what's wrong and what really NEEDS fixin'.
I serviced it once at 50,000 +/-. I had always read to either stay on top of your service OR just let it ride with the fluids that are currently in there (I'm at 152K).

The guy that seemed the most honest to me (and good google reviews) has me at $3300, saxon transmission but only 1 year warranty 12k miles. He said he does the GM vehicles and they mark it up and carry the warranty.

Aside from the lack of warranty- he seems reasonable.
 

swathdiver

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I serviced it once at 50,000 +/-. I had always read to either stay on top of your service OR just let it ride with the fluids that are currently in there (I'm at 152K).

The guy that seemed the most honest to me (and good google reviews) has me at $3300, saxon transmission but only 1 year warranty 12k miles. He said he does the GM vehicles and they mark it up and carry the warranty.

Aside from the lack of warranty- he seems reasonable.
Sonnax parts are cream of the crop. You might ask what exactly is he going to replace before he starts and he may replace other things after inspection. I would want the torque converter upgraded with the new Sonnax parts at the very least. MOST of the time, the first sign of trouble with these things is the plastic solenoids and they can be rebuilt on your kitchen table for $110 plus fluids and the transmission doesn't have to come out. When the torque converter shows signs of trouble, this too can be replaced without spending money on the transmission if caught early enough.

If yours has the external transmission cooler, ask if they are going to flush the lines to remove any debris. He ought to know if he's a pro.

These are not 1970s Turbo 350s, they can be serviced and yours can definitely be serviced at that mileage given its history.
 
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Pointer 21

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I appreciate all the advice. I spoke with him and he said that he would be using a precision Torque Convertor, Sonnax clutches and AC Delco for solenoids etc.
Standing firm that there will be no other costs involved and that he's strictly a transmission shop. Should any other work need to be done, he'll tell me but it's on me to take it to the mechanic to address.

I know I likely have Catalytic convertor issues. About to get costly : /
 

wsteele

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The same online store has OE Y Pipe and cats for just under $800, about a months depreciation on a new rig. :)
 

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