6L80E transmission shift problem

[Larsson]

On 4/30/2021 at 6:06 PM, DeePa said:

Agreed 100 percent. I also think the trans tuning is a big part of it. You don’t hear about the 14s and 15s having this issue. 

You said that the 14s and 15s don't have the torque converter clutch issue? Maybe I'm not so lucky then? Cause my transmission had a little film of alu dust in it. My truck is build in december 2013 but the transmission is build in 2015 (I think).

 

What I'm meaning to say is: do I need to change the transmission software or is it ok to leave it like it is now? 

It drives like new now but I want to run the transmission way past 100000mls without rebuilding it every few years.

[Black02Silverado]

1 hour ago, Larsson said:

You said that the 14s and 15s don't have the torque converter clutch issue? Maybe I'm not so lucky then? Cause my transmission had a little film of alu dust in it. My truck is build in december 2013 but the transmission is build in 2015 (I think).

 

What I'm meaning to say is: do I need to change the transmission software or is it ok to leave it like it is now? 

It drives like new now but I want to run the transmission way past 100000mls without rebuilding it every few years.

To me having the transmission tuned is a good thing and will make it last.  If you firm upt he shifts that increases the life of the transmission by reducing heat and wear.  My 2002 had nice firm shifts and I had it tuned from 10k miles on and it was in great shape at 200k when I sold it.  Speaking of which, I have the new owners contact info. I might contact him to see how it's going.  He purchased it specifically to tow his camper.  This was August of last year.  I would contact Black Bear Performance about tuning it.  To me well worth the money.

[Larsson]

So all the 6L80 transmissions have the bad torque converter clutch problem? And not just the early ones? But why didn't anyone in the aftermarket car parts business have developed a better torque converter for the 6L80? The company who did could earn millions of dollars. I don't hear that dodge or ford have such major transmission design flaws.

 

I always been a chevy truck fan but isn't gm making it very hard for us not to buy a different brand of truck?

[Grumpy Bear]

8 hours ago, Larsson said:

So all the 6L80 transmissions have the bad torque converter clutch problem? And not just the early ones? But why didn't anyone in the aftermarket car parts business have developed a better torque converter for the 6L80? The company who did could earn millions of dollars. I don't hear that dodge or ford have such major transmission design flaws.

 

I always been a chevy truck fan but isn't gm making it very hard for us not to buy a different brand of truck?

 

JMBX...that's the converter with issues. https://www.sonnax.com/tech_resources/845-6l80-6l90-transmission-tech-advisory-consider-an-updated-converter-in-your-next-rebuild

 

Somebody did do something about it. SONNAX. 

 

People have an issue. Converter torches the transmission. Dealership will only use OEM parts in a warranty job. So Joe Owner gets to repeat the mistake because not paying now seems better to him that paying fully later. It's a head scratcher. 

[Larsson]

Does sonnax sell those modified converters or must I buy a sonnax tcc kit and take it to a transmission company together with my bad torque converter? Or do you know other companies who sell "improved torque converters" for my 6L80?

[Grumpy Bear]

1 hour ago, Larsson said:

Does sonnax sell those modified converters or must I buy a sonnax tcc kit and take it to a transmission company together with my bad torque converter? Or do you know other companies who sell "improved torque converters" for my 6L80?

 

You have a PM

[newdude]

...... 

Edited May 17, 2021 by newdude

[Grumpy Bear]

1 hour ago, newdude said:

...... 

 

I PM'd him an email address to a private party that 'may' know something. Not mine. Just respecting the guys privacy. 

[Larsson]

Thanks grumpy bear for the pm. I'll keep that tip in mind.

 

You said that the problem is the jmbx torque converter. I put a heavy duty jmbx in my transmission(HDB85JMBX).  Are the hd versions better or just as bad? Perhaps the heavy duty version usses a different torque converter clutch?

 

This is what I'm going to do. Modify the transmission software and then drive it for 8000mls. Then drain the oil and see if there's debris or alu dust in the pan. If there is then I'm changing the torque converter with a sonnax upgrade. 

[Grumpy Bear]

7 hours ago, Larsson said:

Thanks grumpy bear for the pm. I'll keep that tip in mind.

 

You said that the problem is the jmbx torque converter. I put a heavy duty jmbx in my transmission(HDB85JMBX).  Are the hd versions better or just as bad? Perhaps the heavy duty version usses a different torque converter clutch?

 

This is what I'm going to do. Modify the transmission software and then drive it for 8000mls. Then drain the oil and see if there's debris or alu dust in the pan. If there is then I'm changing the torque converter with a sonnax upgrade. 

That would be a good question for Richard. Email him. 

[Larsson]

I send him an e-mail. Lets wait and hear what he's got so say. Thanks grumpy bear. I'll keep you guys updated.

[Grumpy Bear]

https://www.circledspecialties.com/gm-300mm-hp-6l90-ls-torque-converter-2

 

That could do the trick. Email these guys. This looks like what your looking for. 

Edited May 19, 2021 by Grumpy Bear

[Larsson]

Got an E-mail back from grumpy bear's contact. He says that he machinnes the pump housing if necessary and puts in a transgo tcc kit and a transgo shiftkit. And after install he tunes the transmission with hp tuners. After all of this the transmission works great and stays that way.

 

So I'm going to tune my transmission to prevent any problems in the future.

 

 

[Larsson]

Hi guys,

 

Here's a update of how things are right now. 

 

I tried to find someone in holland who could reprogram my transmission. After a long search I found a guy who works at the gm import dealer. He could help but asked a serious amount of money. So I did the math and bought my own hp tuner hardware. This was only a little bit more expensive than the gm guy asked. But now I can modify my software as often as I want and it's also usefull to read dtc codes and much much more.

Got a tunefile from grumpy bear's contact and used it to modify the stock transmission software. 

 

Now lets hope that the transmission gets to go way past 100000mls.

 

Thanks guys for all the usefull input.

 

[pokismoki]

did you replace the tcc o-ring on the snout of the pump stator when you changed your converter? this o-ring is what locks or seals the clutch fluid off, if its old and cracked or flattened out, it will leak and you loos clutch lock up..

 

you should data log the trans first thing.  the tech guy at the tuning school can help you out too. but you have to spend 185 buck on the transmission book to get free tech support for 1 year.

 

 

Edited July 29, 2021 by pokismoki