6L80e issues / torque converter

[pronstar]

I’m pushing 80k miles on my ‘15 Silverado 5.3

Noticed two big slips recently, I think my torque converter is giving up.

Truck was at a slow roll, I gave it some throttle, revs went right to the limiter and truck didn’t move. I let off the throttle, felt it engage second, and then performed normally.

Worth it to replace the torque converter and hope for the best?
Or start saving for a rebuild/replacement?

Trans is serviced regularly at the dealer, fluid drain/fill/filter every 30k

 

[Runs2rch]

I’m pushing 80k miles on my ‘15 Silverado 5.3

Noticed two big slips recently, I think my torque converter is giving up.

Truck was at a slow roll, I gave it some throttle, revs went right to the limiter and truck didn’t move. I let off the throttle, felt it engage second, and then performed normally.

Worth it to replace the torque converter and hope for the best?
Or start saving for a rebuild/replacement?

Trans is serviced regularly at the dealer, fluid drain/fill/filter every 30k

I bet the dealer has never dropped the pan and changed the filter. They flush and lie.

Do it yourself and swap to the new Mobil 1 blue label fluid.

 

[bk2drvr]

It’s too bad the exhaust Y pipe is where it is. Some GM engineer somewhere is either laughing or ashamed. Hopefully the latter.

Good luck with the trans.

 

[Runs2rch]

It’s too bad the exhaust Y pipe is where it is. Some GM engineer somewhere is either laughing or ashamed. Hopefully the latter.

Good luck with the trans.

The pan comes out without touching the y pipe. You clock it a little toward the passenger side and it comes right out.

Plenty of idiots on youtube posting bad info.

 

[CLdrinker]

Sounds like you better get it to a transmission shop and get their opinion.

 

[bk2drvr]

The pan comes out without touching the y pipe. You clock it a little toward the passenger side and it comes right out.

Plenty of idiots on youtube posting bad info.

I’ll give this a try as I have to do mine soon. Regardless it’s a shitty layout. Thanks for the tip though!

 

[Big B Hova]

Buy an extended warranty asap lol

 

[76 Southwind]

2011 Silverado 5.3 with way more miles. Same symptoms Wish I had paid more attention. Torque converter went out and scattered through the transmission. Not a good ending.

 

[Chili Palmer]

My son just had his trans on his 2016 GMC Sierra 1500 done at 112,000 miles - that cost him $4300. On the other hand, my Allison trans on my 2500 HD has almost 300,000 miles has had regular service and is still going strong.

 

[rivermobster]

Sounds like you better get it to a transmission shop and get their opinion.

Yep.

The only way a torque converter is intermetent, is if you're Really low on fluid.

Sounds like that trans is toast.

 

[snowhammer]

I’m pushing 80k miles on my ‘15 Silverado 5.3

Noticed two big slips recently, I think my torque converter is giving up.

Truck was at a slow roll, I gave it some throttle, revs went right to the limiter and truck didn’t move. I let off the throttle, felt it engage second, and then performed normally.

Worth it to replace the torque converter and hope for the best?
Or start saving for a rebuild/replacement?

Trans is serviced regularly at the dealer, fluid drain/fill/filter every 30k

I plan to do a filter and fluid change with Mobil 1 blue real soon on the Tahoe. Hopefully that will take care of the shudder.

 

[Blubyu]

Needs a transmission 100%! We do two or three of these a week.

Streetsmart Transmission sells a decent unit, fair priced, good warranty. Find an installer and get it shipped out. We do install their transmissions often and have had good luck, only had one come back and it was due to the filter falling out of the valve body. I would install one on my own.

 

[C08H18]

My experience is that GM trans hits an expiration date @ 120K miles.

 

[lbhsbz]

I’m pushing 80k miles on my ‘15 Silverado 5.3

Noticed two big slips recently, I think my torque converter is giving up.

Truck was at a slow roll, I gave it some throttle, revs went right to the limiter and truck didn’t move. I let off the throttle, felt it engage second, and then performed normally.

Worth it to replace the torque converter and hope for the best?
Or start saving for a rebuild/replacement?

Trans is serviced regularly at the dealer, fluid drain/fill/filter every 30k

have you checked the fluid level? Half the people that come to me thinking they need a trans just need a tailshaft seal or something and a few quarts of fluid (at least for now...lol).

 

[ElAzul]

Hopefully it's an easy fix but If you end up needing a trans I used streetsmarttrans for my 6l80e last year and it's been beyond solid and saved me a ton of cash.

 

[pronstar]

Fluid level is good, and looks like new.

I’ve read that the torque converter is a common failure point.

I’m hoping that replacing just that will prevent it from becoming a glitter bomb, taking the tranny with it.

Or is my tranny likely ready to pop regardless?
If that’s the case I’ll run it into the ground and just swap it out when the time comes.

 

[FreeBird236]

Fluid level is good, and looks like new.

I’ve read that the torque converter is a common failure point.

I’m hoping that replacing just that will prevent it from becoming a glitter bomb, taking the tranny with it.

Or is my tranny likely ready to pop regardless?
If that’s the case I’ll run it into the ground and just swap it out when the time comes.

Like Rivermobster said, torque converters are not intermittent.

 

[Riverbottom]

If the trans was serviced and filter changed, most service guys don't change out the seal to the valve body. If the small seal that the filter presses into is not changed it can suck air and causes similar problems. I would drop the pan, pry out the seal, and press in a new one. The seal comes with the filter, but no one goes to the trouble to change it.

 

[Runs2rch]

If the trans was serviced and filter changed, most service guys don't change out the seal to the valve body. If the small seal that the filter presses into is not changed it can suck air and causes similar problems. I would drop the pan, pry out the seal, and press in a new one. The seal comes with the filter, but no one goes to the trouble to change it.

Exactly. Also the dealer is using dex 6 in the 6 speed still. They found it is hydroscopic in these transmissions.

 

[Shlbyntro]

Like Rivermobster said, torque converters are not intermittent.

Tell that to the torque converter in front of my 4R100 that likes to intermittently "stall" at idle in reverse. The truck grunts and takes off like you just dumped the clutch. I just about shit a brick the first time it happened.

All that being said. I would maybe try a filter and fluid change but at this point all you're doing is buying a little bit of time if its anything other than low fluid level. When you're ready, I'd just bite the bullet and do a rebuilt trans with a new torque converter

 

[snowhammer]

I just did the fluid and filter change. Dropped the pan as there is no drain plug. It would be helpful to have an extra set of hands to get the pan out as the exhaust cross pipe runs right under the rear of it.

I had a tough time finding Mobil 1 LV ATF HP blue label at any parts store. I finally called the Chevrolet dealer and sure enough they had it and made a comment of the service bulletin for this issue. I ran enough through to flush the converter and cooler.

Time will tell.

 

[rivermobster]

Tell that to the torque converter in front of my 4R100 that likes to intermittently "stall" at idle in reverse. The truck grunts and takes off like you just dumped the clutch. I just about shit a brick the first time it happened.

All that being said. I would maybe try a filter and fluid change but at this point all you're doing is buying a little bit of time if its anything other than low fluid level. When you're ready, I'd just bite the bullet and do a rebuilt trans with a new torque converter

If it was the converter...

Why does it only do it in reverse?

And at idle too? How does that work??

*Scratching head*

 

[Shlbyntro]

Couldn't tell you, but last I checked automatic transmissions don't slip the clutches, thats what the torque converter is for

 

[LargeOrangeFont]

Friend has a Yukon Denali with a 6l80/90.

It suffered from the shrinking check balls

 

[rivermobster]

Couldn't tell you, but last I checked automatic transmissions don't slip the clutches, thats what the torque converter is for

That's Exactly how an auto transmission works...

It has multiple clutch packs internally, that the valve body controls. The VB applies fluid pressure to each clutch pack to engage or disengage a particular gear or set of gears. They call these planetary gears.

Picture two fans, facing each other. If you turn one fan on, it will make the other fan move. Yes? That's all a torque converter is, but the fans are sealed in it, and instead of air, they use fluid.

Its working 100 percent of the time. Transferring the engine power, into the trans, through fluid movement, in a totally sealed environment.

Late model cars use electronic controlled lock up converters, that eliminate the inherent slip in the converter. This reduces heat as well.

Ever hear of a high stall converter? They work just like a prop does, when you apply a different pitch to it. Pretty simple.

The torque converter is working 100 percent of the time. The internal clutches, work on demand....

They use rubber seals to actuate the clutch pistons. Rubber does not last forever. When it breaks down, the clutch's slip.

The worn clutch material can also cause havoc inside the valve body. The lint from a shop rag can cause havoc inside a valve body. They are Very sensitive indeed!

All kinds of things can cause intermetent issues in an automatic transmission. The torque converter is not one of them.

P.. S. When you install a "shift kit" into a transmission, the whole purpose of a shift kit is to reduce internal clutch slip. If you removed the slip completely, the trans would snap your neck every time it shifts. And the drive shaft, and the motor mounts, and the...

You get the idea.

 

[Shlbyntro]

That's Exactly how an auto transmission works...

It has multiple clutch packs internally, that the valve body controls. The VB applies fluid pressure to each clutch pack to engage or disengage a particular gear or set of gears. They call these planetary gears.

Picture two fans, facing each other. If you turn one fan on, it will make the other fan move. Yes? That's all a torque converter is, but the fans are sealed in it, and instead of air, they use fluid.

Its working 100 percent of the time. Transferring the engine power, into the trans, through fluid movement, in a totally sealed environment.

Late model cars use electronic controlled lock up converters, that eliminate the inherent slip in the converter. This reduces heat as well.

Ever hear of a high stall converter? They work just like a prop does, when you apply a different pitch to it. Pretty simple.

The torque converter is working 100 percent of the time. The internal clutches, work on demand....

They use rubber seals to actuate the clutch pistons. Rubber does not last forever. When it breaks down, the clutch's slip.

The worn clutch material can also cause havoc inside the valve body. The lint from a shop rag can cause havoc inside a valve body. They are Very sensitive indeed!

All kinds of things can cause intermetent issues in an automatic transmission. The torque converter is not one of them.

P.. S. When you install a "shift kit" into a transmission, the whole purpose of a shift kit is to reduce internal clutch slip. If you removed the slip completely, the trans would snap your neck every time it shifts. And the drive shaft, and the motor mounts, and the...

You get the idea.

So care to explain why I have a positive 1:1 engagement at idle with no slip in reverse?? I have to stand on the brakes before it'll "let go"

 

[rivermobster]

So care to explain why I have a positive 1:1 engagement at idle with no slip in reverse?? I have to stand on the brakes before it'll "let go"

Sure!


















Your trans is fucking fubar!
















J/k. Sounds like you may have an electrical issue, with power to the lock up solenoid, for the converter...

What position is the shifter in? How did you measure the output rpm, to know it's the same as the input rpm? I'm doubting this is the case.

But, Let's say for the sake of argument, it actually is in 1:1. You have to stand on the brakes you say?? If this is a Chebby, you have a dual switch brake light switch. One goes to the brake lights, and one goes to the lock up converter. One is normally open, and one is normally closed. Guess which one is which??

Unplug the connector at the switch. Problem fixed? The switch was bad, and was staying closed ALL the time.

This was keeping the lock up converter locked All of the time.

You need a new brake light switch.

For starters...

Not fixed? Is there power at the switch? If you jump it, is there power at the converter?

Let me know, and we can continue to diagnose. If needed.

 

[Orange Juice]

Sure!


















Your trans is fucking fubar!
















J/k. Sounds like you may have an electrical issue, with power to the lock up solenoid, for the converter...

What position is the shifter in? How did you measure the output rpm, to know it's the same as the input rpm? I'm doubting this is the case.

But, Let's say for the sake of argument, it actually is in 1:1. You have to stand on the brakes you say?? If this is a Chebby, you have a dual switch brake light switch. One goes to the brake lights, and one goes to the lock up converter. One is normally open, and one is normally closed. Guess which one is which??

Unplug the connector at the switch. Problem fixed? The switch was bad, and was staying closed ALL the time.

This was keeping the lock up converter locked All of the time.

You need a new brake light switch.

For starters...

Not fixed? Is there power at the switch? If you jump it, is there power at the converter?

Let me know, and we can continue to diagnose. If needed.

My Dodge had a bad brake lite switch issue, and the Transmission did some weird stuff until it warmed up 2-3 minutes.
I had someone follow me down to Dodge, to drop it off, and they told me my brake lights were always on.

They fixed the Brake lite, and couldn’t find a problem with the transmission. I’m 50k miles+ now. If this was the reason, I’m felling relieved the problem is fixed, and I’m not waiting for a grenade.

 

[Shlbyntro]

Sure!


















Your trans is fucking fubar!
















J/k. Sounds like you may have an electrical issue, with power to the lock up solenoid, for the converter...

What position is the shifter in? How did you measure the output rpm, to know it's the same as the input rpm? I'm doubting this is the case.

But, Let's say for the sake of argument, it actually is in 1:1. You have to stand on the brakes you say?? If this is a Chebby, you have a dual switch brake light switch. One goes to the brake lights, and one goes to the lock up converter. One is normally open, and one is normally closed. Guess which one is which??

Unplug the connector at the switch. Problem fixed? The switch was bad, and was staying closed ALL the time.

This was keeping the lock up converter locked All of the time.

You need a new brake light switch.

For starters...

Not fixed? Is there power at the switch? If you jump it, is there power at the converter?

Let me know, and we can continue to diagnose. If needed.

Its a Ford but No arguments there! This transmission has been on its last leg for quite a while. But im quite sure the torque converter is f*cked too.

If you sat in my truck when it did it, you would say beyond the shadow of a doubt that the torque converter is locked, I've even stalled the 7.3 a handful of times when the converter wouldn't let go as i was standing on the brakes.


It takes true talent to stall a 7.3 with an automatic


At the end of the day it all circles back to the same end, a new trans AND converter (when I get around to it)

 

[rivermobster]

Its a Ford but No arguments there! This transmission has been on its last leg for quite a while. But im quite sure the torque converter is f*cked too.

If you sat in my truck when it did it, you would say beyond the shadow of a doubt that the torque converter is locked, I've even stalled the 7.3 a handful of times when the converter wouldn't let go as i was standing on the brakes.


It takes true talent to stall a 7.3 with an automatic


At the end of the day it all circles back to the same end, a new trans AND converter (when I get around to it)

Get a wiring diagram and trace it out.

Merry Christmas!

 

[FreeBird236]

Tell that to the torque converter in front of my 4R100 that likes to intermittently "stall" at idle in reverse. The truck grunts and takes off like you just dumped the clutch. I just about shit a brick the first time it happened.

All that being said. I would maybe try a filter and fluid change but at this point all you're doing is buying a little bit of time if its anything other than low fluid level. When you're ready, I'd just bite the bullet and do a rebuilt trans with a new torque converter

With my limited knowledge of transmissions I should have stayed out of the fray, but before RM ever said anything I was saying to myself, is there anything in there that moves? I've broken fins before, but that wasn't intermittent.

 

[Don Batman]

Torque converter clutch: how it works, symptoms, & cost - Summit County Voice

As a part of the converter, the torque converter clutch locks the engine and transmission, letting them rotate at the same pace This article says more.

summitcountyvoice.com

 

[FreeBird236]

Torque converter clutch: how it works, symptoms, & cost - Summit County Voice

As a part of the converter, the torque converter clutch locks the engine and transmission, letting them rotate at the same pace This article says more.

summitcountyvoice.com

Looks like there's more involved than I realized.

 

[rivermobster]

Looks like there's more involved than I realized.

It depends...

That article was very misleading. Some vehicles have no lock up features. Some have basic speed sensitive lock up function. Some have fully computer controlled lock up functions.

And different manufacturers all do it different ways.

But keep this in mind...

The OP is is experiencing slipping.

Shelby is experiencing a zero slip situation.

They are both blaming the converter, which I don't believe is the culprit in either condition! Lol

Learning to properly diagnose any situation takes having knowledge of the exact vehicle you are working on and a through understanding of the systems involved on that vehicle.

Anything else is called "throwing darts" by those of us in the business. Throw enough darts at the board, and eventually one will hit the mark!

There is definitely more to an automatic transmission than usually meets the eye.

 

[Shlbyntro]

It depends...

That article was very misleading. Some vehicles have no lock up features. Some have basic speed sensitive lock up function. Some have fully computer controlled lock up functions.

And different manufacturers all do it different ways.

But keep this in mind...

The OP is is experiencing slipping.

Shelby is experiencing a zero slip situation.

They are both blaming the converter, which I don't believe is the culprit in either condition! Lol

Learning to properly diagnose any situation takes having knowledge of the exact vehicle you are working on and a through understanding of the systems involved on that vehicle.

Anything else is called "throwing darts" by those of us in the business. Throw enough darts at the board, and eventually one will hit the mark!

There is definitely more to an automatic transmission than usually meets the eye.

I do get what your saying, I do. But I would submit that it is very much a chicken or the egg scenario and regardless of which one came first and compromised the other, I would never do a trans without a torque converter or vice versa.

In my situation at least, it is not a simple electrical issue. It is either A: some kind of mechanical failure within the TC in which case debris could have traveled back into the trans and they both need replaced; or B: hydraulic issues within the trans where the TC is not being fed proper volume and/or pressure which would suggest debris in the valve body which has likely traveled throughout the system and they both need replaced.

Either way, the end result is the same and its really just semantics at this point

 

[rivermobster]

I do get what your saying, I do. But I would submit that it is very much a chicken or the egg scenario and regardless of which one came first and compromised the other, I would never do a trans without a torque converter or vice versa.

In my situation at least, it is not a simple electrical issue. It is either A: some kind of mechanical failure within the TC in which case debris could have traveled back into the trans and they both need replaced; or B: hydraulic issues within the trans where the TC is not being fed proper volume and/or pressure which would suggest debris in the valve body which has likely traveled throughout the system and they both need replaced.

Either way, the end result is the same and its really just semantics at this point

As always, proper diagnosis is key.

 

[pronstar]

Spoke to several reputable shops on the phone, had one local shop (they rebuilt a 4L60 for me) check the truck out.

Unamimous verdict:
Replace the torque converter with an HD unit.

 

[pronstar]

Welp, in she goes tomorrow for a Sonax-upgraded single-disc torque converter. I just hope it doesn’t let go on the drive there…I’ve been driving this thing like a grandma LOL

Have just started to notice some shudder on the tach when it locks-up at low rpm. Still no glitter in the fluid, but I think the filter is gonna tell us something.

And then I get to save up some pennies because our Suburban has the same tranny

Why GM would continue to build a decent tranny saddled with a crappy torque converter with well-known issues is beyond me…

 

[4Waters]

This is what my wife's 4L60E sounded like

 

[pronstar]

View attachment 1086305

This is what my wife's 4L60E sounded like

The G80 “grenady” rear locker has the same pic! LOL

 

[Sherpa]

do a check on 2015 gm transmission problems........... you're gonna find alot of information..................

--the 8 speeds have all kinds of problems in that year too

 

[pronstar]

do a check on 2015 gm transmission problems........... you're gonna find alot of information..................

--the 8 speeds have all kinds of problems in that year too

Yeah I’ve got the 6L80 6-speed.

Most of the info I’ve found, and confirmed with the shops I contacted, centered around the torque converter.

There are definitely upgrades that can be done internally, but I’m trying to avoid opening it up…if the filter is packed with glitter then I’ll have to deal with it.

But in your experience what would you recommend we look at?