Transmission Woes 2020 6l80

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vinnie999

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Hello Everyone! I'm on my 7th Tahoe since the early 90's, and I've driven all of my previous ones in excess of 200k without any major issues. My 2020 has 125k on it, and when I went to leave my house yesterday, it wouldn't move. Drive or reverse were just like neutral. I took another vehicle, and when I came back, I tried it again and it went right in gear. The fluid level is right where it should be and doesn't smell burnt. I drove around the block and it shifted fine but when I got back, I shifted from park to drive several times and after 5 times it went to neutral only in any gear. I ordered a filter and fluid to see whats in the pan, and am having trouble getting my scanner to read it. My transmission scanner just says "can't load". Any ideas?
 

NickTransmissions

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Sounds like a TEHCM problem or broader communication issue across your network of modules. Filter can also be either clogged or cracked at the neck.

There's also this issue, which can produce a no movement condition if both #1 and #5 check balls wear out at the same time.
6L80 No Forward No Reverse Check the Check Balls #automobile #transmissionrepair #6L80

Let us know what you find when you drop the pan.
 
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vinnie999

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Thanks for the reply Nick. I dropped the pan and it was a clogged filter with debris in the pan. After the service, it shifted like new but we both know it's on borrowed time. I searched for a rebuilt online, and when I checked out the reviews for the companies they were awful. It was pretty much the same locally. A new one from GM was going to be about 6k, so I went to the dealer I've been doing business with for years and traded it. They gave me a great trade, and said they were going to auction it anyway. I got a 21 with 39k on it and the threw in a 7/100 warranty
 

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