time to break up with denial…guess who. 6L80!!!

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denalilex

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philadelphia, pa
ok.
torque is bad
clutch release bearing is bad
1-2-3-4 clutch housing is cracked
there is probably more
but it gave me 304,000 miles so i’m not even mad at all. went well beyond the expectancy im grateful

but so it’s getting warmer(lol, well, today was 60, yesterday was like 30, so, it’s getting warmer) & it’s been a few months since i could bear the sight of my tragedy so i bought a high tech cover & i covered it up with as much denial that money could buy.

& i actually let it grow a flat in the driveway.
i do not know who i have become.

anyway, i also somehow got invited to amazon vine so i have like $6k worth of rebuild truck parts i’ve been stockpiling like a pack rat that are keeping me from fitting in my room anymore so its time.

i know weve been over a few of these things before but to be honest im a hot ball of anxiety & for the first time i can say im not looking forward to it. but i wanna do it. &

please can you give me any personal advice where what how who to start
other things to look for
thanks @NickTransmissions i’ve been watching
this may be stupid
do all 6l80s have coolers? i have tow package
mine has always run very cool. like very cool. never tops 130.
i don’t haul except for a 18’ boat a few times & 2 jet skis in the summer.


i have a full garage i have all the tools i have the press i dont have a lift but i have 6 hydro jacks & i’ve gotten by with them before im small i can crawl so ill be good
no the truck doesn’t fit in the garage
just the hood :(


also hope you’ve all been well :’)
(i still can’t summarize my point)
 

KidWgn

Certified Kid Hauler
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St. Louis, MO
ok.
torque is bad
clutch release bearing is bad
1-2-3-4 clutch housing is cracked
there is probably more
but it gave me 304,000 miles so i’m not even mad at all. went well beyond the expectancy im grateful

but so it’s getting warmer(lol, well, today was 60, yesterday was like 30, so, it’s getting warmer) & it’s been a few months since i could bear the sight of my tragedy so i bought a high tech cover & i covered it up with as much denial that money could buy.

& i actually let it grow a flat in the driveway.
i do not know who i have become.

anyway, i also somehow got invited to amazon vine so i have like $6k worth of rebuild truck parts i’ve been stockpiling like a pack rat that are keeping me from fitting in my room anymore so its time.

i know weve been over a few of these things before but to be honest im a hot ball of anxiety & for the first time i can say im not looking forward to it. but i wanna do it. &

please can you give me any personal advice where what how who to start
other things to look for
thanks @NickTransmissions i’ve been watching
this may be stupid
do all 6l80s have coolers? i have tow package
mine has always run very cool. like very cool. never tops 130.
i don’t haul except for a 18’ boat a few times & 2 jet skis in the summer.


i have a full garage i have all the tools i have the press i dont have a lift but i have 6 hydro jacks & i’ve gotten by with them before im small i can crawl so ill be good
no the truck doesn’t fit in the garage
just the hood :(


also hope you’ve all been well :’)
(i still can’t summarize my point)
As far as I'm concerned, automatic transmissions are black magic. They're the only thing I won't open up and work on myself. I say drop the trans and parts off at a shop and go have a drink :rotflmao:
 

89Suburban

Bull in the china shop
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@denalilex JIC, these guys are out by me and are very well regarded for their transmission services/repairs.



 

petethepug

Michael
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07 Yuke Denali Standard. Yes, the Denali comes with a trans cooler from the factory. The 6L80 trans replacement is pretty routine but the important thing is what else you do when it’s extracted.

* Uprated T/C
* Xfer case dog bone mount bushes (4) or 2 new dog bones
* Oil pressure sensor
* 1/2 shift cable kit
* Motor mounts
* Option to swap in ARP Exh Mani bolts
* Rear main seal
* Pan gasket
* Oil pump o ring at mount
* Xfer case fluid swap

If you get all that covered when the trans is out the labor is free or will save you at least $2k if you did it all one by one. It’s usually a 100k major service thing. Drop your Denali off at the Chicken Ranch and have it all done for making it to 300k.
 
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The transmission bench
ok.
torque is bad
clutch release bearing is bad
1-2-3-4 clutch housing is cracked
there is probably more
but it gave me 304,000 miles so i’m not even mad at all. went well beyond the expectancy im grateful

but so it’s getting warmer(lol, well, today was 60, yesterday was like 30, so, it’s getting warmer) & it’s been a few months since i could bear the sight of my tragedy so i bought a high tech cover & i covered it up with as much denial that money could buy.

& i actually let it grow a flat in the driveway.
i do not know who i have become.

anyway, i also somehow got invited to amazon vine so i have like $6k worth of rebuild truck parts i’ve been stockpiling like a pack rat that are keeping me from fitting in my room anymore so its time.

i know weve been over a few of these things before but to be honest im a hot ball of anxiety & for the first time i can say im not looking forward to it. but i wanna do it. &

please can you give me any personal advice where what how who to start
other things to look for
thanks @NickTransmissions i’ve been watching
this may be stupid
do all 6l80s have coolers? i have tow package
mine has always run very cool. like very cool. never tops 130.
i don’t haul except for a 18’ boat a few times & 2 jet skis in the summer.


i have a full garage i have all the tools i have the press i dont have a lift but i have 6 hydro jacks & i’ve gotten by with them before im small i can crawl so ill be good
no the truck doesn’t fit in the garage
just the hood :(


also hope you’ve all been well :’)
(i still can’t summarize my point)
300k miles is outstanding for these and frankly, any automatic transmission. Not sure if all of them have external coolers (they all have heat exchange via the trans cooler inside the radiator) but if your vehicle doesn't have an external cooler, I'd add one...I'd also consider proactively replacing your radiator or having it rebuilt by a radiator shop. If the internal trans cooler in the radiator fails, it will flood your transmission with coolant, destroying it.

As far as getting started, you can watch my 6L80 Teardown and Inspection video - that should give you a solid understanding of what all to check for as well as considerations for overhaul. My 6L80 Info thread will give all the parts and procedures that my 6L overhauls get....Check your area for a good torque converter builder...Many times those folks will also do pump machining and have reconditioned parts for good prices...For example, I always reuse the 3-5-R drum but have the welds at the base reinforced...Only reason I wouldn't is if it's cracked elsewhere or straight up falling apart (I've see examples of this as well).

Don't get nervous about it, these are actually fairly easy transmissions to deal with once you have all the tools you need.
 

j91z28d1

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it makes me sad to see 300k talked about like it's an amazing feat from a gm these days.

but sadly it is, as I see my 2011 slowly falling apart at 150k while my obs never blinked at 300k.

blah.. good luck building the tranny, seems like a good skill to have.
 

Just Fishing

Can't fix stupid
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my 6l80 looked like new inside with 180k on it.
it did have a broken 2-6 wave plate, but it ran and shifted fine.
I did a proactive rebuild after I went through a couple thrust bearings and a crankshaft that was attempting to escape out the front of the engine. :violin2:
I found a plugged transmission cooler as well. :thumbsdown:

So, it came apart to look through, especially since it could have had lube issues in the rear due to the cooler issues.
I found building it a pleasure, not cheap by any means.
Don't skimp, test everything.
If it's questionable, then replace it.
 

Geotrash

Dave
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Richmond, VA
ok.
torque is bad
clutch release bearing is bad
1-2-3-4 clutch housing is cracked
there is probably more
but it gave me 304,000 miles so i’m not even mad at all. went well beyond the expectancy im grateful

but so it’s getting warmer(lol, well, today was 60, yesterday was like 30, so, it’s getting warmer) & it’s been a few months since i could bear the sight of my tragedy so i bought a high tech cover & i covered it up with as much denial that money could buy.

& i actually let it grow a flat in the driveway.
i do not know who i have become.

anyway, i also somehow got invited to amazon vine so i have like $6k worth of rebuild truck parts i’ve been stockpiling like a pack rat that are keeping me from fitting in my room anymore so its time.

i know weve been over a few of these things before but to be honest im a hot ball of anxiety & for the first time i can say im not looking forward to it. but i wanna do it. &

please can you give me any personal advice where what how who to start
other things to look for
thanks @NickTransmissions i’ve been watching
this may be stupid
do all 6l80s have coolers? i have tow package
mine has always run very cool. like very cool. never tops 130.
i don’t haul except for a 18’ boat a few times & 2 jet skis in the summer.


i have a full garage i have all the tools i have the press i dont have a lift but i have 6 hydro jacks & i’ve gotten by with them before im small i can crawl so ill be good
no the truck doesn’t fit in the garage
just the hood :(


also hope you’ve all been well :’)
(i still can’t summarize my point)
I rebuilt a ZF 5hp24 on my workbench a few years ago, which is a close cousin to our 6L80 which is basically a licensed ZF design.

It wasn’t bad at all. I rather enjoyed the craftsmanship of it and love knowing that it was done with great care. You can do it!
 

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