you’ve since probably figured this out but i just went through the entire diagnosing process myself with my gen 1 6l80 & the harsh 2-3 & yes, also noticeable 4-3 downshift….the problem lies solely in the valve body … yes, the compensator feed oil is correct - the problem’s origin lies within the compensator feed valve :… & the cause of the issue is the check balls…. GM built the 6l80s with steel checkballs in the valve body when these trucks came off the factory line…… over time, the steel of the check ball can potentially & in these instances of harsh 2-3, 3-4 - has - resulted in worn spots in the check ball’s bores - which creates just a minute shift in the spacing allotment & there is now excess space in the bore that is supposed to be filled exactly once the hydraulic fluid fills upon the clutch engaging or vice versa & thus, creates the slip that we feel upon 2-3, 3-4 or 4-3… & yes, this is what i’ve come to understand as having the same role as an accumulator, which 4l65s have the same issue which the cause is the cracked pistons, springs or checkballs & replacing those affective components to remedy the issue…. since just replacing the compensator feed valve won’t rectify the issue of enlarged bores - either entire valve body replacement was required or do some searching like i did & get the drop in valve kit….sonnax built & sells what’s called the compensator feed regulator valve kit…. i’ll attach the PN at the bottom. essentially creates like almost an accumulator of sorts & puts an end clip at the valve opening & spring to regulate fluid feed & travel. works as advertised, there are a few different components that could use this kind of attention on these gen 1s… gen 2s(2010-up) now have 8 checkballs as opposed to gen 1s with 7… this is to better disperse the load… be careful with part numbers. some information on the web says replace your separator plate with the updated one with 8 checkballs - if you’re a gen 1, you would need to replace your upper & lower to accommodate as the gen 1s do not have the bore for an 8th check ball. the separator plate looks almost identical. but it isn’t. also - the tehcm pressure switch seals have likely failed as well if these issues have occurred. that’s a cheap, considerably easy when you’re talking about transmission repair tasks. sonnax also offers them with the tools to properly install & seat them. always look up correct bolt layout/locations BEFORE you take anything - but especially the tehcm - off of the vehicle. you’ll also need an e50 external torx bit. here’s the sonnax compensator feed regulator valve kit PN -- 104740-09K here’s th3 zip kit they offer that will address the commonly noticed issues with this trans PN -- 6L45-6L90-ZIP & here’s the seals with the tools included. seals can be bought separately without the tools but you’ll need them do you don’t have them. or you risk puncturing a seal & having to wait truckless til the new ones you’ll have to order - arrive - PN -- 124740TL30 thanks for this video it actually gave me my starting point to eventually pick my way through …. & wound up saving me a whole lot of money.
I’m having the same issue and new rebuilt tried to tune it out with hp tuners but it’s just the worst gear out of all doesn’t matter if I’m in WOT or cruising
What about when you have a two to three neutral out and when you turn the truck off in park and start it back up it works again would that be a TCM issue
I air checked mine and I am getting a werid air leak or something and I have no clue if my teflons are resized to small because I cant get it to seal like you do in another video also what PSI do you use to air check the compensator feed if anyone can help thank you
i only got these 4 - P0842-00 P0872-00 P0877-00 P0989-00 this also told me that my tehcm pressure switch seals had most likely failed & upon pulling my tehcm - def were. the harsh shift typically won’t throw a code… it’s not a computer error - it’s from the steel check balls wearing into their bore over time. there’s a drop in valve kit to repair the issue without needing to replace your whole valve body. if your truck starts slipping severely enough that it reverts into limp mode / commanded 3 - then you’ll get a few codes. mine were saying my pressure switch solenoids were stuck off - it was but a reset of my TCM via peddle method fixed it. i have had my truck parked since & replaced the steel check balls with their new plastic ones & installed the drop in compensator feed regulator valve … replaced the torn seals & my issues are all gone & the trans operates like brand new. sorry if you already figured it out.
If indeed what you say is true it can only be because they think so little of there technicians...... Look my friend, someone put this thing together, it's not quantum physics. Check out the video where the pump is machined in order to rebuild it. The stator has to come out, the gasket and o-ring are in the overhaul kits to. Trust me I worked for GM, when this trans is no longer available in new vehicles the cost of this pump will shoot through the roof, and will not even be available too long after that. I do these videos to help others. I don't make anything from this. I don't give a tinkers dam what uncle general has to say. Oh and this truck is still out there doing just fine. Thanks for watching and don't believe what people say until it jives with what you already know to be true. Only God does not lie or make mistakes. This video and the one that followed were all about my mistake.........Have a good weekend man!
They torque the cast iron portion one way while they hold the aluminum housing and the they tighten it together. That's what they told us when I attended the 6l80 class.
@@liraman71 Thanks, I'll be looking closer at that next time I get one in. I've done several so far without any issues......yet........time will tell. My first was a 6L90, the 3 year warranty just expired last August. Does that same caution statement apply to those too? If so I feel pretty confident that we'll be okay. But I'm still curious about it now, thanks for the input.
you’ve since probably figured this out but i just went through the entire diagnosing process myself with my gen 1 6l80 & the harsh 2-3 & yes, also noticeable 4-3 downshift….the problem lies solely in the valve body … yes, the compensator feed oil is correct - the problem’s origin lies within the compensator feed valve :… & the cause of the issue is the check balls…. GM built the 6l80s with steel checkballs in the valve body when these trucks came off the factory line…… over time, the steel of the check ball can potentially & in these instances of harsh 2-3, 3-4 - has - resulted in worn spots in the check ball’s bores - which creates just a minute shift in the spacing allotment & there is now excess space in the bore that is supposed to be filled exactly once the hydraulic fluid fills upon the clutch engaging or vice versa & thus, creates the slip that we feel upon 2-3, 3-4 or 4-3… & yes, this is what i’ve come to understand as having the same role as an accumulator, which 4l65s have the same issue which the cause is the cracked pistons, springs or checkballs & replacing those affective components to remedy the issue…. since just replacing the compensator feed valve won’t rectify the issue of enlarged bores - either entire valve body replacement was required or do some searching like i did & get the drop in valve kit….sonnax built & sells what’s called the compensator feed regulator valve kit…. i’ll attach the PN at the bottom. essentially creates like almost an accumulator of sorts & puts an end clip at the valve opening & spring to regulate fluid feed & travel.
works as advertised, there are a few different components that could use this kind of attention on these gen 1s… gen 2s(2010-up) now have 8 checkballs as opposed to gen 1s with 7… this is to better disperse the load… be careful with part numbers. some information on the web says replace your separator plate with the updated one with 8 checkballs - if you’re a gen 1, you would need to replace your upper & lower to accommodate as the gen 1s do not have the bore for an 8th check ball. the separator plate looks almost identical. but it isn’t.
also - the tehcm pressure switch seals have likely failed as well if these issues have occurred. that’s a cheap, considerably easy when you’re talking about transmission repair tasks. sonnax also offers them with the tools to properly install & seat them. always look up correct bolt layout/locations BEFORE you take anything - but especially the tehcm - off of the vehicle. you’ll also need an e50 external torx bit.
here’s the sonnax compensator feed regulator valve kit
PN -- 104740-09K
here’s th3 zip kit they offer that will address the commonly noticed issues with this trans
PN -- 6L45-6L90-ZIP
& here’s the seals with the tools included. seals can be bought separately without the tools but you’ll need them do you don’t have them. or you risk puncturing a seal & having to wait truckless til the new ones you’ll have to order - arrive -
PN -- 124740TL30
thanks for this video it actually gave me my starting point to eventually pick my way through …. & wound up saving me a whole lot of money.
Insanely helpful, thankyou for sharing this information and simplifying the diagram to transmission. Very well explained
Best video ever seen. Gracias.
You are the man!!!!
I’m having the same issue and new rebuilt tried to tune it out with hp tuners but it’s just the worst gear out of all doesn’t matter if I’m in WOT or cruising
What about when you have a two to three neutral out and when you turn the truck off in park and start it back up it works again would that be a TCM issue
Mine just started slipping in about 4th and when it downshifts it hits real hard
I air checked mine and I am getting a werid air leak or something and I have no clue if my teflons are resized to small because I cant get it to seal like you do in another video also what PSI do you use to air check the compensator feed if anyone can help thank you
What was the problem here.Why you deleted part2?😢
Where is part 2
Man, it seems like a nightmare.
Where can you find those diagrams for the transmissions
Do you know where i can find the one for the 4l80e
Do you have a video of you rebuilding the pump
No, it's same as 4L60e in many ways.
what dtc did this give you if any?
i only got these 4 -
P0842-00
P0872-00
P0877-00
P0989-00
this also told me that my tehcm pressure switch seals had most likely failed & upon pulling my tehcm - def were.
the harsh shift typically won’t throw a code… it’s not a computer error - it’s from the steel check balls wearing into their bore over time. there’s a drop in valve kit to repair the issue without needing to replace your whole valve body. if your truck starts slipping severely enough that it reverts into limp mode / commanded 3 - then you’ll get a few codes. mine were saying my pressure switch solenoids were stuck off - it was but a reset of my TCM via peddle method fixed it. i have had my truck parked since & replaced the steel check balls with their new plastic ones & installed the drop in compensator feed regulator valve … replaced the torn seals & my issues are all gone & the trans operates like brand new.
sorry if you already figured it out.
at 6:38 looks like the bell has a crack on the left side?
Casting marks.
@@rdick218 Thanks! As a GM wrench turner seen a bunch of those!
This dude sounds like Bill Paxton.
Been doing the 6l80 and 90 transmissions for a long long time, it’s not recommended to take the support off the cover,
If there is any question replace it.
GM says not to disassemble the pump like you showed in the video.
Why?????????
If indeed what you say is true it can only be because they think so little of there technicians...... Look my friend, someone put this thing together, it's not quantum physics. Check out the video where the pump is machined in order to rebuild it. The stator has to come out, the gasket and o-ring are in the overhaul kits to. Trust me I worked for GM, when this trans is no longer available in new vehicles the cost of this pump will shoot through the roof, and will not even be available too long after that. I do these videos to help others. I don't make anything from this. I don't give a tinkers dam what uncle general has to say. Oh and this truck is still out there doing just fine. Thanks for watching and don't believe what people say until it jives with what you already know to be true. Only God does not lie or make mistakes. This video and the one that followed were all about my mistake.........Have a good weekend man!
They torque the cast iron portion one way while they hold the aluminum housing and the they tighten it together. That's what they told us when I attended the 6l80 class.
@@liraman71 Thanks, I'll be looking closer at that next time I get one in. I've done several so far without any issues......yet........time will tell. My first was a 6L90, the 3 year warranty just expired last August. Does that same caution statement apply to those too? If so I feel pretty confident that we'll be okay. But I'm still curious about it now, thanks for the input.
liraman71 correct that is a big no . That pump cover is junk now that he had taken it apart.
eh Richard no speak spanish