alpha_omega
Full Access Member
I thought the exact same thing when I read it. I was like, come on man…I know that YOU know better.
my last 6L80 post :(
- Thread starter denalilex
- Start date
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Just Fishing
Can't fix stupid
I'll add one more little tidbit into my adventure with the 6l80 rebuild.
I ran into an issue that is somewhat well documented with rebuilders.
Apparently a batch of 6L90 1-2-3-4 drums went out with the 6L80 stickers.
That confused the hell out of me when trying to do endplay checks.
I couldn't get the stupid pump to seat!!
Then I remembered the note when watching the mass amount of youtube videos where one of the builders noted that as an "FYI" and to always compare the old part to the new one.
Sure enough, set the new drum next to the old one and I could see the height difference.
the 6l90 has an extra clutch plate or two, and the case is a little longer in that aspect.
In a way it sort of worked itself out,
I had issues with the selective snap rings, and the 2-6 clutch was out of spec.
And I couldn't source one that called out 2-6?!
and the instructions state that if the clutch clearances are wrong, then you assembled it incorrectly and to do it again.
I disassembled and reassembled several times, and it checked out!
So, I ended up using a snap ring from the 1-2-3-4 drum that fit perfectly (and with much better tension), that brought it right into the needed clearance spec.
doing a little mixing and matching I also got that 1-2-3-4 clutches nice and consistent with the rest of the build.
I also noted one youtube video where they ran into a broken wave plate in the 2-6, I had that in my transmission.
No symptoms that I noticed, but it looked like a ticking time bomb if those two broken pieces happened to bind up and fry the clutch.
Picture I posted in my build thread ( https://www.tahoeyukonforum.com/threads/just-fishings-09-tahoe-build-thread.125403/post-1666200 )
I ran into an issue that is somewhat well documented with rebuilders.
Apparently a batch of 6L90 1-2-3-4 drums went out with the 6L80 stickers.
That confused the hell out of me when trying to do endplay checks.
I couldn't get the stupid pump to seat!!
Then I remembered the note when watching the mass amount of youtube videos where one of the builders noted that as an "FYI" and to always compare the old part to the new one.
Sure enough, set the new drum next to the old one and I could see the height difference.
the 6l90 has an extra clutch plate or two, and the case is a little longer in that aspect.
In a way it sort of worked itself out,
I had issues with the selective snap rings, and the 2-6 clutch was out of spec.
And I couldn't source one that called out 2-6?!
and the instructions state that if the clutch clearances are wrong, then you assembled it incorrectly and to do it again.
I disassembled and reassembled several times, and it checked out!
So, I ended up using a snap ring from the 1-2-3-4 drum that fit perfectly (and with much better tension), that brought it right into the needed clearance spec.
doing a little mixing and matching I also got that 1-2-3-4 clutches nice and consistent with the rest of the build.
I also noted one youtube video where they ran into a broken wave plate in the 2-6, I had that in my transmission.
No symptoms that I noticed, but it looked like a ticking time bomb if those two broken pieces happened to bind up and fry the clutch.
Picture I posted in my build thread ( https://www.tahoeyukonforum.com/threads/just-fishings-09-tahoe-build-thread.125403/post-1666200 )
That's one of the reasons I always have the existing drum re-welded. I recall hearing that a while back from a builder buddy of mine but largely forgot about it until now.
Wonder if you initially mixed up the 2-6 clutch snap ring with another one as they will always yield .050" + or - .001 or so...otherwise, not sure why your 2-6 would have been out of spec unless the piston was too tall or short, new clutches and steels or you installed the belville return spring upside down.
Did you replace all the cushion and belville plates?
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Just Fishing
Can't fix stupid
I'm 100% sure I didn't mix them up, I processed each section one by one and kept very organized.
I even kept the plates and clutches in the correct order and the same direction as I worked.
I also don't know if that transmission had been torn down before or not, I assume not but it had a lot of owners before me.
As for the plates, I replaced everything in the 2-6 clutch since the broken part, but I had issues sourcing some things.
I did not touch the big heavy plates at the top.
That 2-6 clutch, I also put it back together with the original steels, installed things every possible direction in an attempt to get it to clearance correctly.
Super weird!
This was also a proactive rebuild, so nothing actually failed in that transmission.
Torn down just because I had a restricted cooler line and a questionable thrust bearing failure in part due to that restricted cooler.
Yea, odd...Not something I have encountered (yet) in the 6L transmissions.I'm 100% sure I didn't mix them up, I processed each section one by one and kept very organized.
I even kept the plates and clutches in the correct order and the same direction as I worked.
I also don't know if that transmission had been torn down before or not, I assume not but it had a lot of owners before me.
As for the plates, I replaced everything in the 2-6 clutch since the broken part, but I had issues sourcing some things.
I did not touch the big heavy plates at the top.
That 2-6 clutch, I also put it back together with the original steels, installed things every possible direction in an attempt to get it to clearance correctly.
Super weird!
This was also a proactive rebuild, so nothing actually failed in that transmission.
Torn down just because I had a restricted cooler line and a questionable thrust bearing failure in part due to that restricted cooler.
Did you measure the thickness of the new frictions?
Perhaps one or two were out of spec (too thick or thin) but not easily noticeable by eye unless you're measuring each one or you happen to notice it when handling them.
Anyway, glad it worked out ok in the end.
Just Fishing
Can't fix stupid
Yeah measured, scratched my head, and measured again.
Also, that 2-6 clutch,
It was off just a little.
Like if there was a thicker/selective steel or clutch, that would have fixed the clearance issue.
Just It's just odd.
Clearances were checked using a dial indicator, and compressed air as well, so maybe that was part of it.
One thing I didn't check was by reinstalling the old piston.
I did use aftermarkets (blue).
I don't recall if I measured those or not
Now that you mention it, the aftermarket piston was probably the problem and what i initially thought. I use National brand pistons which the OEM manufacturer for all GM transmissions since at least the 90s when the bonded steel/rubber pistons first appeared in transmissions.
Nope, you're clearance check method is spot on. I also check clearances with an indicator and air (if you've watched any of my vids where i check clutch pack clearance, that's how I show folks how to do it). The most accurate method IMO.
