Need transmission replaced, anyone done this somewhere other than dealer?

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bdbull

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Transmission is going out on my '15 Tahoe LTZ and I'm starting to research replacement options. Talked with a mechanic buddy of mine today who agreed that it's going and needs to be replaced. He did his own on his '03 Avalanche and said he would help me if I wanted to do it myself. He suggested I research and call around to get some prices on a remanufactured transmission with/without labor to determine if we should attempt it. Has anyone done it themselves or bought a transmission and taken it to a shop to have it installed? Any info appreciated.

Also in some of my research I've read about several reprogrammings that need to happen after replacement, so I'm not even sure if this is something that we can do since we don't have the tools required to perform whatever reprogramming needs to happen.
 

Doubeleive

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TCM has to be relearned so yes a tool to do that is needed, and yes plenty of people have done it themselves and/or bought one from a online transmission dealer as well. shop around prices vary....
 

Oh Kee Pah

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Following along...very interested to see what others might have to say regarding the reprogramming in particular.
Does anyone know what GM's reference of "TCM" means? Transmission Control Module?

Take a look first at the Torque Converter. Have you notice your RPMs jumping up/down 100-300 for no apparent reason? Loss of power, especially uphill ascents? A slipping feeling?
That seems to be the most common failure of the transmission components. I do know that when the torque converter goes, then basically the entire transmission needs to be redone. I also have read that with failing torque converters and new transmissions required, GM vehicle owners are getting warranty and possibly extended warranties to cover the work. Now, what type of transmission the warranty work will cover is up in the air. It might mean that you will have to cough up some extra cash for the top GM transmission. However, I have also heard that a rebuild GM transmission, done at the dealer, comes with a 100k/3yr warranty on it...

I've also read rebuilt transmission costs are around $3,500 from a reputable transmission shop to do the work while GM was $4500-5500.
* This was in a Silverado forum, but should be no different for us really *

I know, not too much help with your initial post, but additional food for thought on this topic.


Safe Travels
 

Bill 1960

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Read the warranty carefully before you put down money. Most reman sources have a lot of restrictions on your rights/ their obligations. In my opinion but the GM warranty is much better.
 

Jeff_

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$4500 to $5500 for GM to do it? Damn!
Hit up RPM transmissions and see what they charge. The TR6060 from my Camaro can be fully built for 1200+hp and cost less than that.
 

Doubeleive

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Following along...very interested to see what others might have to say regarding the reprogramming in particular.
Does anyone know what GM's reference of "TCM" means? Transmission Control Module?

Take a look first at the Torque Converter. Have you notice your RPMs jumping up/down 100-300 for no apparent reason? Loss of power, especially uphill ascents? A slipping feeling?
That seems to be the most common failure of the transmission components. I do know that when the torque converter goes, then basically the entire transmission needs to be redone. I also have read that with failing torque converters and new transmissions required, GM vehicle owners are getting warranty and possibly extended warranties to cover the work. Now, what type of transmission the warranty work will cover is up in the air. It might mean that you will have to cough up some extra cash for the top GM transmission. However, I have also heard that a rebuild GM transmission, done at the dealer, comes with a 100k/3yr warranty on it...

I've also read rebuilt transmission costs are around $3,500 from a reputable transmission shop to do the work while GM was $4500-5500.
* This was in a Silverado forum, but should be no different for us really *

I know, not too much help with your initial post, but additional food for thought on this topic.


Safe Travels
yes transmission control module, it's internal to the transmission without it being learned to the vehicle it won't shift
 

swathdiver

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Transmission is going out on my '15 Tahoe LTZ and I'm starting to research replacement options. Talked with a mechanic buddy of mine today who agreed that it's going and needs to be replaced. He did his own on his '03 Avalanche and said he would help me if I wanted to do it myself. He suggested I research and call around to get some prices on a remanufactured transmission with/without labor to determine if we should attempt it. Has anyone done it themselves or bought a transmission and taken it to a shop to have it installed? Any info appreciated.

Also in some of my research I've read about several reprogrammings that need to happen after replacement, so I'm not even sure if this is something that we can do since we don't have the tools required to perform whatever reprogramming needs to happen.
GM dealers will put in a certified reman for 3-5K that's warranted for 100K and can be serviced nationwide.

What exactly is going wrong with your 6L80? Often times, the first thing that needs doing is the solenoids replaced and this can be done on your kitchen table without removing the transmission for about $120 plus fluids. More involved than this, I suggest you get the Shop Notes by Art Landeck and the Shop Manual and watch every video on the 6L80/6L90 on youtube, especially Precision Transmissions.
 
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bdbull

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Take a look first at the Torque Converter. Have you notice your RPMs jumping up/down 100-300 for no apparent reason? Loss of power, especially uphill ascents? A slipping feeling?
What exactly is going wrong with your 6L80? Often times, the first thing that needs doing is the solenoids replaced and this can be done on your kitchen table without removing the transmission for about $120 plus fluids. More involved than this, I suggest you get the Shop Notes by Art Landeck and the Shop Manual and watch every video on the 6L80/6L90 on youtube, especially Precision Transmissions.
It has problems going up the slightest incline if it needs to downshift. It has trouble downshifting and then seems to jump back and forth between gears. It actually does this a lot around 45MPH or so. It's like it can't decide which gear it wants to be in. It will also just shake and shudder sometimes right after a shift.
I also have read that with failing torque converters and new transmissions required, GM vehicle owners are getting warranty and possibly extended warranties to cover the work. Now, what type of transmission the warranty work will cover is up in the air. It might mean that you will have to cough up some extra cash for the top GM transmission.
Tell me more on this. Are people getting the replacement transmission and procedure done under some kind of warranty? It's a '15 with 123k miles so it's well out of any kind of warranty.
 

swathdiver

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It has problems going up the slightest incline if it needs to downshift. It has trouble downshifting and then seems to jump back and forth between gears. It actually does this a lot around 45MPH or so. It's like it can't decide which gear it wants to be in. It will also just shake and shudder sometimes right after a shift.

Tell me more on this. Are people getting the replacement transmission and procedure done under some kind of warranty? It's a '15 with 123k miles so it's well out of any kind of warranty.
Have you checked your fuel pressure at idle and under load by chance? I would definitely have it diagnosed with a Tech-2, but of course, just about all transmissions shops are going to say, yep, it's shot and needs to be rebuilt. They shy away from doing partial repairs and for good reason, sometimes.

Yours sounds like a good candidate for having the solenoids in the TECHM rebuilt. Lots of guys on here have done it. My favorite part of my BlackBear tune is in how the way the transmission performed afterwards, it never hunts for a gear.
 

houstontaylor

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Transmission is going out on my '15 Tahoe LTZ and I'm starting to research replacement options. Talked with a mechanic buddy of mine today who agreed that it's going and needs to be replaced. He did his own on his '03 Avalanche and said he would help me if I wanted to do it myself. He suggested I research and call around to get some prices on a remanufactured transmission with/without labor to determine if we should attempt it. Has anyone done it themselves or bought a transmission and taken it to a shop to have it installed? Any info appreciated.

Also in some of my research I've read about several reprogrammings that need to happen after replacement, so I'm not even sure if this is something that we can do since we don't have the tools required to perform whatever reprogramming needs to happen.
A local general auto repair shop just replaced my 2003 Tahoe transmission with a remanufactured one from GM which includes a 3-year warranty from GM. It was $4,200.
 
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