GM 6L80 Transmission Information Thread

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Geotrash

Dave
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New Question for Nick or Robert (transgo)
I am thinking of relocating my trans external fan forced cooler (for a couple of
reasons). I see that ICT billet has a nice adapter that mounts to my 6l80e
and I can just use only AN lines - my preference.
They make it in a 6an and 8an..
My question is there any advantage or disadvantage to go with the larger 8an
lines from trans to radiator to ext cooler then back to trans ??????
IDK if that changes pressures that would affect anything.. I would think the larger line
would flow a little bit more volume is why I ask.
Right now I'm running the factory steel lines in and out of trans case... with #6 lines
between radiator & ext cooler.
My mods are in signature
I don't know the answer off-hand, but you should be able to easily calculate that based on the ID of the smallest points in the system. The only thing the larger lines would potentially do is 1/ reduce the frictional losses within the hoses, but that's only a tiny fraction compared to any choke points in the fittings and ports on either end of each line, and 2/ give you larger and less restrictive fittings on the hose ends. But if the ID of the fittings at the radiator, at the external cooler, or at the transmission, are smaller than the larger AN hoses and fittings, the larger size AN won't really matter.
 

Foggy

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I don't know the answer off-hand, but you should be able to easily calculate that based on the ID of the smallest points in the system. The only thing the larger lines would potentially do is 1/ reduce the frictional losses within the hoses, but that's only a tiny fraction compared to any choke points in the fittings and ports on either end of each line, and 2/ give you larger and less restrictive fittings on the hose ends. But if the ID of the fittings at the radiator, at the external cooler, or at the transmission, are smaller than the larger AN hoses and fittings, the larger size AN won't really matter.
I was kinda thinking the same thing... I've done several fuel system projects and
that's kinda the case - except you can just crank up the pressure at the pump and/or
regulate it with external regulator.. So bigger is better IF you need "flow"
Always appreciate your feedback !!!

Anyone else want to chime in ???
 

CTX-SLPR

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Drove it for around 30min with the gauge under the wiper, max temp was 189 on the DIC which matched the TECHM sensor value when I had a scan tool on it. Now I have done the HPTuners changes to pressures, slips, and a bit of turning on the 2-1 and 3-1 shift timings so I'm not strictly the same as stock anymore.

Out of gear idle: ~75psi
In gear idle: started at ~75psi but as it got warmer it dropped to 60psi

Driving around it was around 90psi with spikes to 120-160psi during shifts or as high 210psi if I got on it

The gauge seemed very responsive like the TECHM was commanding different pressure for upshifts, downshifts, and lockup and the regulator/controller was responding. I did see a few brief pressure drops on downshifts but things felt normal. I have some videos but it won't let me upload them.
Does anyone one else have HPTuners 6L80 mods and a pressure gauge to check what kind of behavior they are seeing? I’m leaning towards just putting the ZIP kit in and driving it to see what happens. Worst case I have to pull the whole trans out and I’m just out whatever trans fluid I spill around the clean catch basin (fluid has less than 1500mi on it) assuming I don’t find any new bits in the pan.
 
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